As part of a two-week state-wide crackdown on the enforcement of seat belt laws, 425 municipal police departments will be on the lookout for drivers not wearing their seatbelts from 9 tonight until 5 a.m. tomorrow.

The effort, called Operation Nightlife, is aimed at reducing the number of overnight fatal crashes in which victims did not wear seat belts. During the past year, more than 40 percent of fatal crashes in which the victims weren't wearing seat belts occurred during the overnight hours, according to the state Department of Transportation.

Of the 400 overnight crash deaths during the past year, more than half of the victims were not wearing seat belts, PennDOT statistics show.

Under Pennsylvania law, all front seat passengers must wear seat belts and children ages 4 to 8 must be restrained in an appropriate booster seat. Children ages 8 to 18 must use a seat belt regardless of where they sit in a vehicle. Seat belt laws are secondary, which means drivers can be fined only if cited for another traffic violation.

In addition to seat belt laws, the state's primary child passenger safety law requires that children until age4 be properly restrained in a child safety seat. The fine for not using child safety or booster seats is $100. The fine for not complying with seat belt laws is $60.