One or more thieves in a four-wheel-drive Toyota smashed through the barred front window of a College Park gun store Sunday and fled with nearly $11,000 worth of weapons, most of them military-style, semiautomatic assault rifles, Prince George's County police said.

In all, police said, 14 rifles and three pistols with a total retail value of $10,626 were stolen from the Schelin Gun Shop in the 9800 block of Rhode Island Avenue. The thief backed a stolen Toyota 4Runner through the store's front window shortly after 6 a.m., police said.

"They went through the glass, the bars, everything," a Prince George's police detective said. Before officers could respond to the store's burglar alarms, the weapons had been scooped off racks behind the counter and the Toyota was gone, he said. "It was just run in, grab and go."

Police said they found two mud flaps in the store that had been ripped from the Toyota when it was backed through the window. About four hours after the theft, police said, they spotted a red Toyota 4Runner with torn mud flaps abandoned in Hyattsville.

The Toyota had been reported stolen Dec. 19 in Silver Spring.

Although firearms are a popular item for burglars, the number of rifles stolen in Sunday's burglary was unusually large, according to law enforcement officials. Police said yesterday that arrests did not appear imminent in the case.

Police and a federal agent said yesterday that the assault rifles probably will be sold illegally on the streets at prices far higher than their retail value.

"That's exactly why the theft took place," said David Troy, the agent in charge of the federal Bureau of Alcohol, Tobacco and Firearms office in Falls Church. "These guys aren't going to Montana to hunt deer. These weapons were stolen so they could be sold on the street. And when it's all done, someone's going to make themselves a bundle of cash."

The illegal demand for such weapons is so great, especially among drug traffickers in the Washington area, that "I'll guarantee you {the rifles} are out on the street now," Troy said. "They're not sitting around in someone's trunk. They were sold and out on the street within 24 hours."

The store's owner, John Schelin, could not be reached yesterday. Damage to the store was estimated at $13,000.

Authorities declined to describe the stolen rifles, except to say that most were military-style, semiautomatic assault weapons.

In a semiautomatic rifle, unlike a bolt-action rifle, a new round of ammunition is loaded into the chamber instantly each time a shot is fired. This allows the rifle to be fired as fast as the trigger can be pulled.

Many semiautomatic rifles sold to civilians are nearly identical in design to military rifles, except that the military versions also can be fired on full automatic, like machine guns.

Although it is illegal, a skilled machinist or gunsmith can convert a semiautomatic rifle into an automatic rifle. The potential for such a conversion is one reason that civilian-model assault rifles are popular among criminals, authorities said. "If you've got a weapon that's $500, $600 retail, then you're going to take that to the black market and double that price easily. You might even get more," Troy said.

Federal law requires a buyer of such a weapon to approach a licensed gun dealer, present identification and fill out a background questionnaire, Troy said.