Convinced that their three-day manhunt was over, police cornered a man in a gymnasium storeroom in Anne Arundel County yesterday morning and interrogated him for five hours before realizing that their captive was a look-alike and that fugitive Daniel Dennis Collins was still at large.

The resemblance was "uncanny," said police spokesman Daniel McCarthy, who examined the suspect while holding a photograph of Collins. But, in the end, police were forced to admit that although the faces were similar, the men's fingerprints were different.

Collins, 17, described as armed and dangerous, remains the prime suspect in one rape and three assaults since he escaped from a Howard County hospital on Saturday, police said. He was awaiting trial on five rape charges when he was taken to the hospital in Columbia for an X-ray.

Police surrounded the gymnasium at the Cedar Knoll School, part of a federal juvenile detention center on Jolly Acres Drive near Jessup, at 9 a.m. yesterday, and they captured the look-alike suspect in an adjacent storeroom. Police said the man refused to talk to them for several hours but eventually said he was Tony Anthony Townsend, 25, and no relation to Collins.

Police spokesman McCarthy said, "I myself was standing no more than three feet from the guy. The similarities are remarkable. But perhaps Collins' complexion is a little lighter."

Police charged Townsend, whose address was not known, with breaking into the school and a nearby motel. He was being held in the Anne Arundel County jail with bond set at $5,000.

Officials at Cedar Knoll said they first became suspicious when the night supervisor saw a man wandering behind the school Sunday night.

Before school opened yesterday, day supervisor Burke Munford said he and other officials searched the building and saw a man's feet protruding from a storage room near the school gym. The man appeared to be sleeping.

State police and U.S. Park Police were summoned, and they surrounded the building. Two officers went into the building and approached the man, who by then was awake, McCarthy said. A state trooper called out: "Dan, stop. Do not go out the window," McCarthy said, and the man was taken into custody without resisting.

The man was not armed, police said, but he wore clothes similar to those Collins was believed to be wearing when he escaped. Police believe Collins has suffered a cut on the hand, and the man had a fresh cut on his left hand. He was disheveled, unshaven and covered with burrs, they said.

He was handcuffed and taken to a second-floor interrogation room at the state police barracks in Jessup, where investigators from five police departments involved in the hunt for Collins tried to positively determine the man's identity.

"Some were saying yes, it is him; some were saying they were pretty sure, and others were saying they weren't convinced," McCarthy said. An employe from the Waxter Children's Center, a juvenile detention center in Laurel, who had dealt with Collins about three years ago, was called in and told police he did not think it was Collins.

This conclusion was later supported by an employe from Clifton T. Perkins Hospital Center, the maximum-security state mental hospital in Jessup where Collins had been confined since August. So police took the suspect's fingerprints to an expert with the Howard County police, who confirmed, about 2:30 p.m., that they had the wrong man.