PANORAMA CITY (CBS) — A man has reportedly  been killed in an accident involving a motorcyclist on the San Diego (405) Freeway.

The accident occurred at Roscoe Boulevard in Panorama City, according to Erik Scott of the Los Angeles Fire Department.

The CHP tells CBS2 and KCAL9 that a motorcyclist may have struck a homeless person or pedestrian on the freeway.

All southbound lanes of the 405 were closed for several hours creating a traffic nightmare.

A SIG Alert was issued.

It was unclear if the motorcyclist was injured.

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