MALIBU, Calif. — Traffic was snarled on Pacific Coast Highway in Malibu Monday due to a mud and rock slide that blocked both sides of the roadway.

The slide was reported about 11:30 p.m. Sunday on PCH at Big Rock Drive, according to the California Highway Patrol.

The road was shut down in both directions while Caltrans crews worked to clear the debris. The result was a frustrating morning commute as drivers sought alternate routes. Further confounding motorists was the simultaneous closure of Topanga Canyon Boulevard from PCH to Grand View Drive, also due to a rockslide, eliminating another major thoroughfare in the area.

One lane was reopened about 9 a.m. Monday, with traffic alternating in each direction, the Los Angeles County Sheriff's Department reported.

There was no immediate timeline for when the rest of the road might reopen.