With the number of hit-and-run cases reaching what officials called epidemic proportions, a state official joined Wednesday with local officials and advocates to urge passage of a program creating a “Yellow Alert” system to get help from the public.

Assemblyman Mike Gatto, D-Burbank, and Councilman Mitch Englander urged the state Senate to approve AB 47 and ask Gov. Jerry Brown to sign it into law allowing alerts to be broadcast on freeway signs to help identify those who flee from the scene of a traffic accident.

“There are 20,000 hit and run cases in Los Angeles each year,” Gatto said at a news conference on the steps of City Hall. “This is not just a Los Angeles problem. It’s statewide. Every week you see stories about hit-and-runs.

“Most people believe it is wrong to leave someone by the side of the road. It is a crime that does not reflect our values.”

Englander called the rate of hit-and-runs an epidemic and noted the city no longer calls them “accidents.”

“These are crimes,” Englander said. “Once you leave the scene, you become a felon.”

Gatto has introduced a number of measures dealing with hit-and-runs, including automatic suspension of a driver’s license and increasing the statute of limitations from three years to six years.

Englander said the city needs state help to bring in more potential witnesses to identify hit-and-run drivers and take advantage of the technology that is available.

As part of that, the city is upgrading its ATSAC system — automated traffic surveillance and control — to use digital cameras that can be moved remotely to follow the action of a crash scene and get enhanced images.

Also supporting Gatto’s measure is Damian Kevitt, who lost his left after being hit by a driver who fled the scene of the crash.

“I was lucky,” Kevitt said. “I just lost a leg and not my life.

“Since then, I have become a grass-roots advocate for changing the laws. I have become passionate about the subject.”

However, Don Rosenberg, whose son was killed in a hit-and-run incident, said he is not convinced the new Gatto law will do anything.

“It’s another feel-good bill that closes the door after all the horses have left,” Rosenberg said. “None of these bills do anything to attempt to prevent hit-and-runs. They only work to catch and punish the offender after people have been seriously injured or killed.”