A D.C. Superior Court grand jury has indicted six men, including a locksmith, in what police described yesterday as the largest-and possibly the most sophisticated-car theft ring ever broken up in Washington.

Police said the suspects are charged in a scheme involving the theft of at least 40 late model luxury cars-including Thunderbirds and Cadillac Eldorados-from parking lots and streets throughout the Washington area. Many of the cars were stolen from areas near the Pentagon and Crystal City, police said.

The cars were then driven to Southeast Washington, where they were stripped of their parts and abandoned, according to Officer Joe Hoover, who supervised the D.C. police investigation.

The grand jury charged the men with various offenses related to the stolen car operation. The charges covered a period from November, 1976, to last April.

According to police, one of the cars stolen, a 1977 Lincoln Continental Mark V, was valued at $14,000. The victims have so far recovered about $60,000 from their insurance companies in connection with the thefts. Hoover said.

The cars were stolen and stripped exclusively for their parts," said Hoover, who is with the sixth police district's auto theft unit.

According to Hoover, four members of the group allegedly drove around the metropolitan area until they came upon a luxury car with the parts they wanted to steal, loke large, expensive tires or citizen's band radios.

Hoover said that a screwdriver would be used to pry loose the key cylinder from one of the car doors. The cylinder, Hoover said, would be taken to a locksmith, who is among those indicted. At that point, a key would be made to fit the car-door lock.

The ring seemed to have a preference for Ford Motor Co. cars, Hoover said, because the door keys on Fords, Mercurys and Lincolns also fit the car ignitions.

According to Hoover if the suspects targeted a General Motors car, they would remove the key cyclinder from the trunk because that key would then fit the car's ignition.

The "lock trick" was used in 80 per cent of the cases, Hoover said. Otherwise, the suspects would allegedly start the cars some other way.

"They were wizards, I'll tell you that," Hoover said.

The stolen cars were usually driven to a parking lot behind an apartment building on 37th Place SE., where the cars were stripped and abandoned. Hoover said.

Frequently, residents would call the police after they heard the noise of lug wrenches and cracking glass behind their building, but the suspects "would get away" before the police arrived. Hoover said.

According to Hoover, the suspects then sold some of the parts to a used car dealer, who also indicted in connection with the operation.

Depending on the shape of tires and their condition for example, the used-car dealer allegedly bought a set of four tires for about $100, and then resold them for as much as $400. Hoover said.

Hoover said police began to stake out the Southeast area last spring when they discovered several abandoned cars, all of which had lock cyclinders removed.

Hoover said that one night last April, he approached the suspects as they were loading alledgedly stolen parts into their won car, but they escaped, leaving their own car behind.

The car, a 1966 Plymouth was reported stolen to police, Hoover said. The owner was traced and was one of the six men named in the 77-count indictment, handed down by the grand jury on Oct. 20.

The six men charged by the grand jury with various counts of unauthorized use of a vehicle, receiving stolen Paul Henry Tibbs, 18, of 440 15th property and grand larceny were St. N.E.: Eddie A. Leonard, 18, of 700 12th St. S.E. Andre Leo Holley, 23, of 1345 Monroe St. N.W., and Larry Thompson, 19, of 1604 E St. N.E.

Also indicted were James M. Johnson, 35, the operator of a used-car lot in the rear of a grocery store at 1655 Benning Rd., N.E., and Willie Henry Jr., 25, operator of a locksmith shop at 2001 Benning Rd. N.E.