A 31-year-old man who killed his parents in Bethesda seven years ago escaped yesterday from a hospital for the criminally insane and threatened a motorist in Howard County with a makeshift weapon before being shot by police and recaptured, authorities said.

Brian Bechtold, fled from Clifton T. Perkins Hospital in Jessup yesterday afternoon, wielding a pointed piece of steel, and led Howard County police on a foot chase to Sherwick Court where, according to police, he "threatened the life" of the motorist before being shot.

He was listed in serious condition last night at the Maryland Shock Trauma Center in Baltimore.

The bodies of Bechtold's parents, George W. Bechtold, 54, and Dorothy Bechtold, 63, were found in their locked Hillandale home on Feb. 21, 1992, hours after Brian Bechtold walked into a police station in Port St. Joe, Fla., and told authorities he had killed them.

After firing a shotgun at his parents, he said, he drove to Texas and Florida.

He later pleaded guilty in Montgomery County Circuit Court but was found not criminally responsible because he was suffering from a mental illness at the time. He was found to be paranoid schizophrenic and was to be confined until doctors determined he was not a danger to himself or others.

Richard Fragala, clinical director of Perkins, said that in his escape yesterday afternoon, Bechtold, wielding a 15-inch piece of steel from an ironing board, ordered a nurse to unlock the steel door leading from his medium-security ward.

He then fled downstairs to a lobby filled with visitors and staff members and ran out the door, Fragala said. Outside, according to Howard police, he failed in an attempt to get into a woman's car on the grounds and ran on. Police said they tried to stop him nearby, using pepper spray to no avail. He then confronted a motorist in a pickup truck.

The hospital said that after that confrontation, Bechtold was shot in the right arm and leg and flown by helicopter to the trauma center.