ROCKVILLE, Md. (AP) - As the sniper slayings terrorizing the Washington area have spread beyond the suburbs, so has the radius of law enforcement agencies preparing for the next strike.

Police chiefs in Maryland and Virginia communities up to 40 miles from the nearest connected shooting have beefed up patrols, approved overtime in advance, canceled leaves and installed extra phone lines.

Maryland's two largest cities, Baltimore and Frederick, sent their top police officials to a regional briefing Friday by a multi-agency task force investigating the sniper attacks that have killed eight people and wounded two since Oct. 2.

"Obviously, you don't want the responsible person or offender to slip through the cracks. By having a coordinated effort, you try to maximize the effort you're putting out there," said Frederick County Sheriff James Hagy.

Participants wouldn't discuss specific strategies. Prince William County, Va., police Chief Charlie Deane said his department had contact with the sniper task force and ran "what-if" scenarios for days before Wednesday's sniper killing of a man at a gas station in Manassas.

The perpetrator of another fatal shooting at a gas station near Fredericksburg on Friday eluded pursuers, but coordination played a key role in the rapid, swarming police response that halted midday traffic on area expressways while investigators searched white vans and trucks like those seen leaving at least two crime scenes.

There have been no shootings in Charles County, about 25 miles south of Washington, but it is just south of the county where the sniper wounded a 13-year-old boy on his way to school. That was enough for sheriff's officials to preapprove overtime and set up a tip line that can be made active if needed.

Anne Arundel County, about 20 miles east of Washington, has made similar arrangements. Administrative duties have been reshuffled to maximize the time patrol officers spend on the street.

Charles Moose, the Montgomery County police chief who heads the sniper task force because five of the deaths were in his county, said the Metropolitan Washington Council of Governments had arranged conference calls among its 18 member jurisdictions.

The council drafted a blueprint for coordinated emergency planning after the Sept. 11 terrorist attacks. In addition to meeting regularly to share intelligence and strategies, the member police chiefs are linked by an electronic system that alerts them simultaneously _ by pager, telephone and e-mail _ to incidents of regional interest.

The response to the shootings has spread beyond the council region, though. Baltimore isn't a member, and neither are Anne Arundel and Charles counties.

Nor is Culpeper County, Va., which borders Spotsylvania County, scene of the latest killing Friday. Sheriff H. Lee Hart said Friday he had not talked with the sniper task force but he was aware of the threat.

"I have not canceled all leave, but we've been increasing our overtime at a right rapid pace," he said.