BEAVERTON, Ore. - Passersby jumped into action after seeing a runaway TriMet bus in Beaverton Sunday, climbing aboard and administering CPR on the driver, who was unconscious from some kind of medical emergency, authorities said.

The driver, whose name was not immediately released, was taken to Providence St. Vincent Medical Center, which was just a few feet from where the bus finally came to rest. His condition was not immediately available, but TriMet officials said he is in very bad shape. The man is in his late 50s.

According to Beaverton police Officer Jessica Hull, it all started when the TriMet bus was seen slowly crossing three lanes of traffic on Southwest Barnes Road near Southwest Baltic Avenue about 12:15 p.m. with the driver slumped over inside. No one else was inside the bus, which jumped the sidewalk and ran up a dirt hill before coming to rest just feet from the hospital's day care center.

Several people tried to get inside the bus as it was moving but were only able to climb aboard after a retired TriMet bus operator who happened to be in the area got the door open, Hull said.

Doreen Cannon, a Realtor, was on her way to show a home when she came upon the scene. She got out and started performing cardiopulmonary resuscitation on the driver, who was not breathing, she said.

At some point, a doctor from the nearby hospital was also called over to the scene and joined her in the effort to keep the man alive, Cannon said.

After paramedics arrived, the man was taken to the hospital, she said.

"It was very scary," Cannon said. "You never know if the person is going to live or die, and that's the hardest part. But at least you give them a chance."

No one else was injured during the incident, Hull said.

"I'm just worried about the man," Cannon said. "And I just keep seeing his face, and I hope he lives."