A truck fire Monday afternoon forced the closure of several lanes of southbound Interstate 5 near Del Mar Heights for less than an hour.

About 1:45 p.m., California Highway Patrol officers responded to a report of a commercial truck with flames in its open bed on the southbound I-5, just north of Interstate 805.

Three right lanes of the freeway were blocked as a result of the fire, according to Caltrans San Diego, but all lanes were reopened by about 2:40 p.m.

The driver of the truck was not injured, according to CHP Officer Mary Bailey.

There was no information on what caused the fire.

— City News Service