The row house at 6221 Osage Ave. and its bizarre inhabitants are gone now. So are their neighbors. Their homes on both sides of the street have been reduced to charred skeletons of brick and steel, reminiscent of a war zone.

But the questions about what happened May 13 on Osage Avenue will haunt this city for months, for the events of that day represent one of the great urban tragedies of the decade.

The story of how a once-peaceful, middle-class neighborhood became a battlefield and site of a fire that raged out of control for six hours is one of official inaction and overreaction, miscalculation and failed strategies, human fears and human suffering, death and destruction.

The statistics are devastating: 11 dead, including four children; 53 homes destroyed; 250 left homeless; an estimated $8 million in damages.

They suggest a host of troubling questions:

Did a neighborhood have to be destroyed to save it from a small group of radicals? What caused the fire that engulfed two city blocks and threatened others? Why did police bomb a row house in a crowded, urban area? Why did firefighters wait before trying to control the blaze? Why weren't children saved? Was there no other way to deal with an admittedly difficult situation?

The answers to some questions began to emerge last week as Mayor W. Wilson Goode and other city officials, often giving conflicting accounts, explained their actions on May 13, and as reporters reconstructed events with other eyewitness reports. But other questions may take weeks to answer.

The events began long before dawn Monday when Police Commissioner Gregore J. Sambor, a stoic Ukrainian with 35 years of police experience, ordered members of MOVE, a radical black group, to evacuate the row house.

"Come and get us. We ain't got a . . . thing to lose, so come on down and get us," came back the reply from a MOVE loudspeaker.

The small band of self-described "back-to-nature" revolutionaries, all of whom used "Africa" as a surname, had lived on the block for more than three years, harassing neighbors with harangues from the rooftop about city officials. For months, neighbors watched them fortify the house. They boarded up windows; filled sandbags with dirt; hauled tree trunks, railroad ties and steel plates inside the 19-by-46 foot row house. They built a crude but surprisingly sturdy bunker on its roof. They told neighbors over their loudspeaker that they had stockpiled weapons.

Why the city allowed an armed fort, which proved able to withstand a 12-hour police assault and an estimated 10,000 rounds of police bullets, to be constructed in west Philadelphia is unclear. MOVE was known to be a dangerous organization. A police officer was killed in a 1978 confrontation with the group. Nine MOVE members were convicted in that slaying.

District Attorney Edward Rendell wrote Goode a 16-page memo last year saying there were legal grounds to issue search warrants for MOVE members. But as late as May 1, Goode, responding to angry complaints from MOVE neighbors, said that he knew of no legal grounds for arrest.

Police strategists studied the house for 18 months and placed it under surveillance. On Sunday, May 12, they evacuated all residents of surrounding blocks. But they apparently underestimated how well the row house was fortified. Plans revolved around forcing MOVE members out of the house with tear gas. But during an 80-minute shootout early Monday, tear gas canisters bounced off the structure.

Two seven-member police teams tried to attack from adjoining row houses. After finding the basement walls too thick to penetrate, the teams moved to upper floors, hoping to open holes in the walls for an attack. They discovered that MOVE members had constructed bunkers of log-cabin-like walls, fortified with steel plates, within the house.

One police team was pinned down by MOVE gunfire from inside the row house for more than 90 minutes when it penetrated a wall; the other was pinned down for six hours. Police succeeded in pumping tear gas through a second-floor wall, but one official speculated to The Philadelphia Inquirer that MOVE members were hiding in basement "catacombs," covered with wet burlap to withstand the gas.

Police also tried to bring a large crane with a wrecking ball to the scene, hoping they could use it to smash a hole in the house. But they could not figure out how to maneuver it down the narrow neighborhood streets and anchor it without exposing the operator to gunfire.

As the day wore on, the crude rooftop bunker, built partly with trees cut by city workers in a nearby park, became an increasing concern. Originally, officials hoped to blow it off the roof with fire hoses. Tons of water were shot at it from two water cannon, but the structure didn't budge. As long as the bunker remained, officials feared, MOVE members could keep police at bay. Concern grew as night approached. Goode said police feared that MOVE had dug tunnels under adjoining houses and might blow up the whole block.

The most critical hours of the all-day police siege occurred between 5 p.m. and 7 p.m. During this period two far-reaching decisions were made: first, to drop an explosive device on the house; second, to let the ensuing fire burn. The three key players in these decisions were Police Commissioner Sambor; Fire Commissioner William C. Richmond, a veteran of 25 years of firefighting; and City Director Leo Brooks, a retired Army major general whom Goode had hired to be his top staff assistant.

All were on the scene, and Goode, who remained in City Hall, allowed them to make basic decisions.

Goode and his subordinates have given conflicting accounts of key activities between 5 p.m. and 7 p.m. But based on public statements by officials and a lengthy reconstruction of events by a team of Philadelphia Inquirer reporters, here is what happened:

Sambor and Brooks began discussing blowing a hole in the roof in midafternoon. The idea wasn't new. At least 18 months earlier, police bomb experts were assigned to study photographic blowups of the MOVE rooftop. They had tested explosives for weeks at the city police academy in preparation for such an attack.

At 4 p.m., Police Lt. Frank Powell, head of the bomb squad, was told to make an explosive device. It took him less than 30 minutes. He used two pounds of Du Pont Tovex, an explosive gel, one blasting cap, a fuse and a fuse ignition. All were placed in a small canvas bag.

Tovex is generally used only in mining or quarry operations where it is placed in holes drilled in rock, and Du Pont officials have expressed surprise when told by reporters that it was used in an open-air blast.

Brooks informed Goode of the device at 5:10 p.m., and of the plan to drop it on the row house. The word "bomb" was never used to describe it, he later said. Fire Commissioner Richmond was told of the decision, but no effort was made to call in more firefighting equipment.

At 5:27 p.m., Powell, leaning out of a state police helicopter, dropped the canvas bag on the house. About 45 second later, a huge explosion shook the neighborhood, rattling windows for blocks and sending debris 100 feet in the air. Television cameras showed black smoke emerging from the rooftop within minutes.

But Powell told the Inquirer that he saw no fire from his helicopter, only a football-sized hole in the roof. The bunker, which the device was supposed to destroy, remained largely intact.

By 5:50 p.m., fingers of flame were visible. Sambor maintains that MOVE members started the fire with gasoline inside the house. He said the explosive device was "not incendiary by nature." Richmond, however, has refused to take a position on what started the fire, and the police commissioner's assessment has come under wide questioning.

Some have charged that police must have been aware of gasoline and other flammable material in the house. On May 12, for example, MOVE members had boasted over their loudspeakers that they had spread gasoline over their house and adjoining ones. Photos taken May 13 showed at least one gas can on the roof.

In any event, a decision was made let the fire burn, in hopes that it would burn the bunker or smoke MOVE members out of their stronghold. "I made the recommendation, and it was concurred in by the fire commissioner," Sambor said Thursday.

At about 6:00 p.m., more than a half hour after the device was dropped, a water cannon was trained on the fire. The blaze soon spread to adjoining houses. The first call for more firefighting help was sounded at 6:55 p.m.; subsequent alarms went out at 7:25, 8:02, 8:27, 8:47 and 9:35.

The blaze, driven by a light wind, wasn't controlled until ll:27 p.m., after threatening blocks of west Philadelphia. Firefighting efforts were hampered by gunfire and reports of gunfire, according to Richmond, who said, "We're firefighters, not infantrymen."

Early in the week, Goode reported that police had exchanged gunfire with four persons in an alley behind the burning row house during the early hours of the fire, strongly implying that two of them may have escaped. There were never signs of a manhunt, however, and Sambor said Thursday that police had been fired on but hadn't fired back. Two of those in the alley, Ramona Africa, 29, and Birdie Ward Africa, 13, were captured, and hospitalized with burns. Ramona Africa is being held on $3.2 million bond.

In the wreckage of 6221 Osage, investigators found 11 bodies, four of them children. They also recovered two shotguns, a rifle, two handguns, a large quantity of spent and unspent cartridges, and cans that once contained gasoline and propane gas. Medical examiners found no bullet fragments in any of the bodies.

No tunnels, machine guns or other heavy weapons, which police said MOVE had used in the shootout, have been discovered. One disturbing note, written by a MOVE member, was recovered from the rubble. It said:

"The cops will be coming for us. Don't be impressed with their number. Pick them out one by one."