The seizure of 13 high-powered weapons, including a 9 mm machine gun, a four-barrel .357 magnum derringer and 10 other fully loaded firearms, prompted renewed calls by D.C. police officials yesterday for stricter gun control laws in other states.

Yesterday's seizures bring to 497 the number of firearms confiscated in the District since the beginning of this year compared with 325 firearms at the same time last year, police said.

"We've had more than a 50 percent increase in the seizure of firearms this year," Assistant Chief Isaac M. Fulwood Jr., the department's second-in-command, said in an interview yesterday. "Couple that with the increase in violence and narcotics trafficking -- that's alarming," he said. "It begs for some kind of resolution.

"D.C. has a strict gun control law but the absence of some kind of national control of firearms makes us look like we're just whistling in the wind. In other words, D.C. by itself can't solve the problem."

Police gave these accounts of the two separate incidents spaced 12 hours and four miles apart:Two D.C. officers stopped two Virginia men in a Lincoln Continental at 4:30 a.m. yesterday at 14th and L streets NW after a prostitute alleged that the men had aimed a gun at her. After arresting the men for assault with a deadly weapon, the officers found 10 firearms in the car, including two 9mm semiautomatic handguns, one 10mm semiautomatic handgun that police said is rare, three .357 magnum revolvers, one 12-gauge pump shotgun, two .38-caliber revolvers and one .22-caliber derringer pistol.

All the firearms were fully loaded and 216 rounds of ammunition were seized, police said. The 10mm has been on the market about a year and police had difficulty yesterday locating ammunition with which to test fire it, police sources said. About 4:30 p.m. Wednesday, undercover police officers arrested five men -- three of whom were from Florida -- in a parking lot at Mayfair Mansions-Paradise Manor, two Northeast apartment complexes notorious open-air drug markets. Riding in a dark blue Ford was a Florida man armed with a loaded Interdynamic 9mm Luger machine gun and in the back seat, another man had a four-barrel .357 magnum derringer. Police also seized $576 in cash, a .30-caliber semiautomatic carbine, 37 rocks of crack, a cocaine derivative, with a street value of $1,600.

"This vividly depicts the problem we're experiencing with firearms coming in from other jurisdictions," Capt. William White III, a police spokesman, said yesterday.

"You're talking about two jurisdictions {Virginia and Florida} that don't have the stringent type of gun laws that the District of Columbia imposes on its citizens and it clearly depicts the frequency with which exotic weapons are being brought into the District," White said.

In the District, which has one of the most stringent gun control laws in the country, possession or sale of firearms is illegal. In Maryland a seven-day waiting period is required before purchase of a gun so that police can run a criminal background check. But in Virginia, West Virginia and North Carolina, no waiting period or background checks are required. Florida has the most liberal gun laws in the nation, which include allowing residents to carry concealed weapons.

Arrested at 14th and L streets yesterday and charged with assault with a deadly weapon, carrying a pistol without a license and carrying ammunition without a license were Christopher Fryer, 37, of 18714 Fuller Heights Rd., Triangle, Va., and James M. Saylor, 24, of 5500 Holmes Run Pkwy., Alexandria.

Arrested at Mayfair-Paradise and charged with possession of a machine gun and possession with intent to distribute cocaine were Ronald Ruff, 30, of Miami; Willie James Ruff, 22, of Tampa, Fla.; Randy Ruff, 32, of 1300 Congress St. SE; Rick D. Ellis, 31, of Plant City, Fla.; and Harold A. Bennett, 32, of 4919 Jay St. NE. All five were held without bond.

Staff writer Nancy Lewis contributed to this report.