SEATTLE -- King County Metro Transit is checking all its bus cameras after recording systems failed to capture shootings in downtown Seattle.
One bus driver was shot and wounded Monday morning by Martin Duckworth, 31, who was then killed by police as he boarded a second bus.
The onboard surveillance systems failed to record either shooting.
The agency suspects hard-drive errors in the digital recording systems on both buses, but the situation is being investigated. Metro has been testing Wi-Fi technology that might alert transit supervisors to a camera outage.
All the cameras will be inspected in the next several days, under an order from County Executive Dow Constantine.
The cameras have not been regularly inspected, but Metro says they will now be examined every 6,000 miles, at the same time brakes, engines and other parts undergo routine maintenance.
Metro began using in-bus cameras in 2008.
Bothell-based Apollo Video Technology, Metro's video-surveillance supplier, declined to comment Friday and referred questions to Metro.
Under one early contract, Metro paid $685,000 to equip 145 buses, according to an Apollo statement at that time. That's an average of $4,700 per vehicle.
Since then, the number of equipped buses has grown to 550, or about 40 percent of the fleet, and is to hit 50 percent this year. Cameras are funded largely by federal Homeland Security grants, Metro says.
In the last 18 months, Metro says, it has pulled video records 4,000 times for law enforcement or news organizations. Cameras have helped police find several criminals.
Police and Metro supervisors say they have gathered abundant evidence of last week's gun violence.
Duckworth shot the driver, DeLoy Dupuis, after being asked to pay his fare. Dupuis has wounds to his cheek and arm.