LOS ANGELES (CBSLA.com) — Waves of heavy rain led to flooded freeways and an increase in accidents in Southern California overnight, California Highway Patrol officials said Monday.

Between midnight and 4 a.m., the CHP reported 41 collisions in Los Angeles County, compared with 28 collisions during the same period a week ago Monday, CHP Officer Alex Rubio said.

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Flooding closed all but the express lanes of the northbound and southbound Harbor 110 Freeway from Redondo Beach Boulevard to the Glen Anderson (105) Freeway in Gardena. By 5 a.m., only the No. 5 far right lane was flooded.

Flooding was also reported as debris filled drains on the Ventura (134) Freeway transition to the northbound Golden State (5) freeway in the Griffith Park area, CHP officials said.

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In Orange County, the rain hit after midnight but the first major accident was at 4:50 a.m. when a vehicle overturned and rolled down a ditch on the eastbound Riverside (91) Freeway at Harbor Boulevard, CHP Officer Denise Quesada said.

The CHP reported flooding at 5 a.m. in south Orange County on the northbound Santa Ana (5) Freeway just south of the northbound San Diego (405) Freeway.

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