A man shot his parents in their Upper Marlboro home yesterday and held his critically wounded father hostage for two hours before killing himself, Prince George's County police said. His father died several hours later.

Police said they were still trying to figure out why the gunman, identified by neighbors as Eric Kyle Morrow, 27, shot his parents inside their home in the 11000 block of Winsford Avenue, sparking a standoff with scores of hostage negotiators and SWAT team members that abruptly ended when he stepped outside, stood behind a cedar tree in the side yard and shot himself in the head.

The gunman's father, John James Morrow, 59, was shot in the chest and arm, police said. He was flown by helicopter to Washington Hospital Center, where he died last night.

Morrow's mother, Judith A. Morrow, 57, was shot in the face and arm. She was taken to Prince George's Hospital Center, where she was listed in critical condition, said Capt. Mark Brady, a Prince George's fire department spokesman.

According to neighbors, Judith Morrow stumbled out of her home about 1 p.m., bleeding heavily from her wounds. She then crossed the street in front of her cul-de-sac and knocked on the door of the Chowbay family.

When Danny Chowbay answered, Morrow was on her knees. "She couldn't hardly speak," said Olivia Chowbay, Danny Chowbay's daughter. "Dad said, 'What happened? What happened?' But all she could say was, 'My husband.' "

The Chowbays called 911, and police arrived soon after with a team of negotiators, several sharpshooters and two armored personnel carriers. Authorities sealed off the two-block street to traffic and surrounded the Morrow house, where the gunman and his father were.

Negotiators made contact with Eric Morrow by telephone and talked to him intermittently during the standoff, said Sgt. Gary Cunningham, a police spokesman. Several times, Eric Morrow appeared at the front door and held a gun to his head before going back inside.

Shortly before 3 p.m., Morrow stepped outside, put the gun to his head and fired, killing himself instantly, police said.

Police said they recovered a gun but declined to describe it. They also declined to give a possible motive for the shooting.

Neighbors said the Morrows had lived in the neighborhood longer than just about anyone on the block.

Eric Morrow lived with his parents off and on over the past decade and would visit often. But neighbors said they didn't know much about him or his parents.

"We'd see them out in the yard, raking leaves and washing their cars, but that's about it," said Olivia Chowbay. "Eric was very quiet--he didn't seem like a troublemaker to me."

Staff researcher Bobbye Pratt contributed to this report.