RIVERSIDE – Law enforcement agencies in Riverside County will be stepping up patrols Thursday night and through the Fourth of July weekend to crack down on drunken drivers and other traffic violators.

Beginning at 6 p.m., the California Highway Patrol will initiate its “maximum enforcement period,” posting as many officers as possible on freeways and unincorporated county roads to catch impaired drivers and speeders.

During the CHP's 2007 Fourth of July MEP, officers arrested 39 motorists for DUI in Riverside and San Bernardino counties, according to the Highway Patrol, which logged two traffic-related fatalities on Inland Empire roads in the last holiday period.

This year's MEP ends at 11:59 p.m. Sunday.

During the long holiday weekend, all of Riverside County's 30 municipal police agencies, in addition to the sheriff's department, will be increasing traffic patrols and DUI checkpoints in the county's “Avoid the 30 DUI Campaign,” according to Riverside police Chief Russ Leach.

“Too many people still don't understand that alcohol, drugs and driving don't mix,” he said. “Impaired driving and its consequences are not accidents. There are too many deaths and injuries, and too many innocent victims. Impaired driving is everyone's problem, and we all need to take steps to stop it.”

In 2006, 1,597 people died in alcohol-related crashes in California, and 31,099 were injured, according to statistics.

Riverside-area CHP commander Capt. Tom McCreary said that in addition to watching how motorists handle their vehicles, CHP officers are now paying closer attention to what motorists are doing inside their vehicle.

“If they need to make or take a call, drivers must remember to keep their hands on the wheel, not on the phone,” McCreary said. “And drivers under 18 must refrain from using the cell phone when they're driving a car.”

Under the state's new wireless phone regulations, which took effect Tuesday, drivers under 18 are prohibited entirely – except in emergencies –from using cell phones while driving, and adult drivers must use a hands-free device to operate a mobile phone. The ban doesn't apply to passengers.

Violators will be slapped with a $20 fine for the first offense and $50 for every offense that follows.