A city bus carrying 31 people plunged off a bridge here and plowed through the outer edge of an apartment roof this afternoon after the driver was shot by a passenger. The driver, and a person suspected of shooting the driver, were both killed, the police said. The 29 others were injured.
The two-section bus was just starting to cross Aurora Avenue Bridge, which spans the Lake Union ship canal, about 3:10 P.M. when the driver was shot by a passenger, the police said. The bus, heading south, jumped a lane of northbound traffic, hit a van, then crashed through a guardrail and fell 50 feet, landing upright in an apartment garden in the Fremont district, an area of residential buildings, restaurants and businesses.
Police officers did not disclose a motive for the shooting. They said that two people were involved, and that the second person was among the injured taken to the hospital. The gun was recovered at the hospital, the police said.
Witnesses described a scene of panic as people with broken bones and bleeding cuts tried to crawl out of the bus. Rescue officials pulled out several people who were stuck in the bus.
Mr. Badgley said he had seen two injured people on the roof of the apartments. When aid units arrived, they gave emergency treatment to people who could be seen on the apartment roof.
All the passengers were injured, fire department officials said. Fifteen of the injured were in critical condition tonight and 10 were listed in serious condition, said a Fire Department spokeswoman, Sheila Strehle.
The driver, whose name was not released by the police, was thrown from the bus, fire officials said.
The bus is a two-compartment vehicle with the two units held together by an accordion-like mechanism. It usually carries 120 passengers. Had the bus traveled another quarter-mile or so, it would have fallen several hundred feet and landed in the water. But because the crash happened at the low end of the bridge, the bus landed on ground.
Dan Williams, a spokesman for Metro Bus who arrived at the scene within minutes of the crash, said the bus was not smoking when it landed. Fire Department officials said there no fire on board. But they expressed amazement that the bus had landed upright.
''Nothing like this has ever happened, that I know of,'' Mr. Williams said. Had the accident occurred two hours later, during rush hour, it is likely that the bus would have been full of people, he said.
The front of the bus, its window shattered, came to a rest against a pine tree in a garden next to the apartment. A large section of the roof of the two-story apartment -- the part that hangs over the outside of the building -- was broken away in the crash, as was a deck. But the police said they believed no one in the apartment was injured.
Mr. Badgley called rescue units, and said it took at least 10 minutes for help to arrive. But Fire Department officials said units arrived within 7 minutes. Before the authorities came to the scene, some of the injured helped other people get out of the bus, Mr. Badgley said.
One of the bus compartments was shattered and crumpled.
The bus came to a rest just a block or so from one of Seattle's best-known sculptures, the Fremont Troll, a large concrete image of a troll underneath the bridge.