The hunt for a sniper shooting at cars along a northern California freeway intensified as fresh clues emerged in the case, according to police.

The California Highway Patrol said Wednesday they have uncovered new evidence connected to the nighttime shootings along Interstate 680 that have been reported over the last two months, according to FOX San Francisco affiliate KTVU.

They wouldn't disclose details about what evidence they've found.

The sniper reportedly has been firing a pellet or BB gun at vehicles in the dark. No one has been hurt or killed in the attacks.

"They've established a pattern," said Officer Miguel Andrade. "If you can catch them during the act and if somebody calls right when it happens and we see something because we are in the area, I think we'll be able to catch him."

The number of incidents now stands at 45 since the middle of March. More motorists have been coming forward to report that they have been shot at, police said.

Andrade said some shots have been fired from open spaces and parking lots along I-680. The Highway Patrol has increased its police presence in the area with both uniformed and undercover officers, KTVU reported.

About 15 of the shootings have taken place in the past three weeks, according to KTVU. A silver Range Rover was among five vehicles hit last Saturday night with a BB gun. The pellets shattered the passenger window, but the three people inside escaped unharmed, the station said.

Click here for more on this story from KTVU.com.