LOS ANGELES (CBS) — Starting this week, don’t let the sun go down on you or your child without wearing a seat belt — or it could cost you hundreds of dollars.

The Los Angeles County Sheriff’s Department warned on Monday that effective immediately through June 5, drivers and passengers caught without a seatbelt will face a fine of a minimum $142 for a first-time violation. And the cost is even steeper for children under 16, who will be assessed a $445 fine for the first violation.

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The crackdown comes as the 2011 Click It or Ticket campaign gets underway for the next two weeks.

Nighttime passengers are among the least likely to buckle up and most likely to die in crashes when unrestrained. Almost two-thirds of those who died in nighttime crashes nationwide in 2009 were not wearing seatbelts, which explains why nighttime enforcement is a priority of this year’s campaign, the sheriff’s department said.

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“Lives are saved when people wear their seatbelts,” Sheriff Lee Baca said.

“California’s current seat belt use rate of 96.2 percent is an all-time high, but that still leaves nearly one million people who are not buckling up,” said Capt. Shaun Mathers of the Sheriff’s Risk Management Bureau. “In order to save lives, citations will be issued without warning.

“It’s not just about avoiding a costly ticket; it’s about keeping the ones you care about alive,” he added.

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