U.S. Customs and Border Protection agriculture specialist at the Los Indios International Bridge intercepted live wood-boring insects in packaging material that appeared to have been treated according to international standards, according to an agency release.

The insects were collected on Aug. 25 from two different tractor-trailers using wooden pallets for the transportation of stainless steel sheets arriving from Mexico, CBP said.

The insects were identified as live beetles from the Scolytidae family that are known to attack and kill live trees, the release stated. The shipment was returned to Mexico and a penalty was issued to the company, CBP said.