Speeding vehicles killed or injured 340 people in this city in 2002. Those alarming numbers, coupled with a barrage of complaints from residents, led authorities to apply for a grant from the state to buy six mobile digital traffic speed signs.

Next week, Oakland police will deploy the signs across the city.

"We don't know where the speeders are," said Lt. David Kozicki, head of the traffic operations section. "These signs will tell people to slow down and we can then look at the data collected and put officers in certain areas."

The signs, which tell passing drivers how fast they are going as part of a campaign called "Project Oaktown Slowdown," were on display Wednesday in the Oakland Coliseum parking lot.

The signs will go up next week after further training of officers, who will be able to analyze data and driving patterns recorded by the devices so officers can be dispatched to write tickets or make arrests. The signs will then be redeployed in areas as complaints are logged.

Kozicki said the signs will initially be located throughout the city, possibly one in each of the City Council districts. "We have a long list of communities that say they want them," he said.

Residents citywide have complained vigorously about speeders. Some neighbors have held rallies on street corners, while many block clubs petitioned for speed bumps.

In the Fruitvale district and East Oakland, children have been struck and killed while crossing streets, prompting officials to deploy additional officers to monitor areas or install traffic lights.

City Councilmember Jean Quan (Montclair-Laurel) said speeders are a problem in her district, where streets from the hills are long, steep and winding. "We hope people will think twice about speeding," said Quan, who would like to see the signs up at least twice a year on all of the downhill streets. Some of the biggest offenders are parents heading for schools, she said.

The signs also can be used as message boards for missing children or other alerts and warnings connected with engineering or law enforcement, similar to the statewide system used by police during an Amber Alert, when motorists are asked to look for a certain vehicle in connection with a missing child.

"These are the only message boards we will have in Oakland, so they're very useful," said Kozicki.

Funds were provided through a grant from the state Office of Traffic Safety. The signs cost $12,000 apiece, said Mark J. Bertacchi, regional coordinator for the agency. "These signs have proven to be effective," Bertacchi said. "More speed means more injuries or deaths."

In 2002, the most recent year for data, Oakland recorded1,850 traffic injuries and fatalities, Bertacchi said. Some 340 were speed-related, he said, and there were 310 hit-and-run cases and 246 incidents during evening hours. Oakland was the first city in the Bay Area to use the speed-monitoring devices, in the early 1980s, Kozicki said.

Similar units in Arizona are able to take photos of license plates, and drivers are sent notices. However, those are not in use in California.