Two District Heights men were killed yesterday when their car crashed into a tree during a high-speed police chase that began when the men drove past a police barricade and onto the route of Israeli Prime Minister Menachem Begin's motorcade from Andrews Air Force base.

Police officials said the incident was apparently unrelated to Begin's presence here, but it could not be learned last night why the men refused to stop as police pursued the car for more than two miles along the Suitland Parkway and into the District.

Investigators said, however, that the license plates on the car were registered to a different vehicle owned by a friend of the two victims.

The men, identified as Wayne A. Hoffman, 21, of 7127 Halleck St., the driver, and William B. Clements, 29, of 2209 Ramblewood Dr., were killed about 5:30 p.m. when their car struck a tree at Martin Luther King Avenue and South Capital Street.

D.C. police said the car dashed through a security roadblock at Branch Avenue and onto Suitland Parkway just minutes before the Begin motorcade was due to reach that point, and then drove past another checkpoint at Naylor Road.

A U.S. Park police cruiser began the chase, which reached speeds up to 90 miles an hour, and followed the car to the District line.

D.C. police then picked up the pursuit which continued along Stanton Road and Alabama Avenue SE to Martin Luther King Avenue and South Capitol Street where the crash occurred.