UNION CITY (CBS SF) — Hundreds of surgical masks that were apparently thrown from the back of a truck onto southbound lanes of I-880 in Union City caused a traffic jam Wednesday afternoon as some drivers stopped to gather the masks, according to authorities.

The incident was first reported by CHP at approximately 1:40 p.m. when authorities received calls about a white truck stopped on the freeway. A white or Hispanic male on the bed of the truck reportedly threw multiple boxes of masks onto the freeway into lanes of southbound 880 near the Whipple Avenue exit.

The masks were described as thin medical masks, according to CHP. There were approximately 1,000 that ended up on the roadway.

CHP said that some drivers were stopping their vehicles and trying to collect the masks, which have become a desired commodity during the coronavirus pandemic.

At one point, two CHP vehicles stopped traffic so a Caltrans sweeper could pick up the masks that had collecteded on the shoulder of the freeway.