Man on top of dump truck causes traffic delays on Highway 101 in San Mateo

SAN MATEO, Calif. (KGO) -- A bizarre incident unfolded on Highway 101 on Tuesday afternoon near Highway 92 in San Mateo, shutting down multiple lanes of traffic.

It's not clear what led up to this, but police surrounded a dump truck on the freeway with a man who had gotten out and climbed on top of a pile of what looked like gravel or asphalt in the back.

RELATED: Armed suspect surrenders to police after hours-long standoff at Oakland business

For a moment it looked like he was going to give up and surrender.

He then appeared to throw whatever was in the back of the truck at officers, and so they moved in and arrested him.

He was then taken away on a stretcher.