From Thursday through Sunday between 8 p.m. and 2 a.m. on about 175 miles of roads and highways in the area, drivers enter the zone of "Operation Spider."

In the most recent crackdown on traffic violators, "Operation Spider" weaves its web over roads with the largest number of severe accidents in five counties -- Prince George's, Montgomery, Anne Arundel, Baltimore and Howard.

The "spiders" are patrol cars covering the roads, and the "web" is the joint effort by county and state police.

"It's not a game. We're not trying to trap people. We're identifying the roads," said Chief Bernard D. Crooke of the Montgomery County Police Department.

The roads are 10 to 12-mile stretches identified by the Maryland Deparment of Transportation as having more than 15 accidents per mile during a recent three-year period.

The operation, funded by the federal government, began last Thursday. According to Sgt. Carl Schwarzel of the Montgomery County police force, the "Operation Spider" team in Montgomery County alone issued 94 tickets in the first four days.

The number of traffic accidents dropped dramatically in 1973 when the state made 55 m.p.h. the maxinum speed limit, but the figures have been inching up since then, said Dan McCarthy of the Maryland State Police.

The special patrols are looking for instances of drunk driving, speeding, improper passing, following too closely and failing to obey traffic signals. They have alerted judges and prosecutors in the district traffic courts to expect more cases.

The state's Transportation Safety Division provided $172,100 in federal highway safety funds for the operation, which will last 24 weeks. Crooke said the operation might be able to get more funding after that.

The enforcement teams will be added to regular traffic patrols, with the county police on overtime and the state police troopers taken from the Alcohol and Speed Enforcement Unit.

The high-accident sites in Montgomery County are Connecticut Avenue from the D.C. line to Aspen Hill Road; Montrose and Randolph roads from Seven Locks Road to Georgia Avenue; Piney Branch Road from the Takoma Park line to Prince George's County line; New Hampshire Avenue from Prince George's County line to Clifton Park Lane; Georgia Avenue from the D.C. line to Norbeck Road.

In Prince George's County the sites are Allentown Road from Old Ford Road to Branch Avenue; Branch Avenue between Accokee Road and Allentown Road; New Hampshire Avenue from the D.C. line to Piney Branch Road; Riggs Road and Powder Mill Road from the D.C. line to U.S. 1; U.S. 1 from the North Brentwood -- Hyattsville line to the Howard County line.

Other roads may have higher overall accident rates, according to police, but they do not have as many accidents causing fatalities or injuries.