An opossum was found at Honolulu Harbor on Friday morning by workers offloading a cargo ship from San Diego.

The workers chased it to a trash container at about 3:30 a.m., where it was held until the arrival of agricultural inspectors.

Opossums are native to North America and regarded as an invasive species in Hawaii, where they could pose a threat to the environment and carry infectious diseases.

The captured opossum, whose origin remained unknown, underwent testing for rabies Friday, state officials said.

Scott Enright, chairman of the state Board of Agriculture, praised the workers for their swift action in containing the animal.

Agricultural officials conduct periodic training sessions with air and sea carriers pertaining to handling invasive species. “We need everyone’s eyes, especially at the ports,” Enright said.

Opossums are omnivorous, eating a variety of food, including insects, fruit, bird eggs and rats.

According to the state Department of Agriculture, several opossums have been captured in Honolulu in the past several years, including one in Kakaako near the U.S. Immigration and Naturalization Office along Ala Moana Boulevard in July. Another was caught in a cat trap at a Sand Island warehouse in July 2012.

In August 2011 an opossum was discovered in a shipping container as it was unloaded in Ward Center. Also, two opossums were found in 2005 — one inside a military cargo airplane at Hickam Air Force Base and the other in the mail receiving area at the U.S. Postal Service facility at Honolulu Airport.

Anyone who sees an illegal animal in Hawaii is asked to contact the state’s toll-free hotline, 643-PEST.