LOS ANGELES (CBSLA) — An explosion and fire involving a big rig occurred at a shipping yard at the Port of Los Angeles Monday morning.

April 15, 2019. (CBS2)

The fire was reported at 9:57 a.m. in the 600 block of Harbor Boulevard, just north of the Vincent Thomas Bridge, the Los Angeles Fire Department reports.

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Firefighters said a large 18-wheeler was involved in the fire, along with “some type” of explosion.

The blast blew out the windows of at least four units at a nearby apartment building, the fire department reports.

Social media users reported that the explosion shook their homes.

The truck was taking the cargo container to a ship for export to another country, accordion to port spokesman Phillip Sanfield.

Operations at the port were not impacted by the incident.

There were no serious injuries.

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It’s unclear what caused the explosion or what cargo the semi-truck was transporting at the time.