A dock worker was killed and another was injured when a tire on a heavy piece of equipment “blew up” at the Port of Los Angeles Wednesday morning, according to authorities.

The accident happened at a container terminal on Pier 300 around 7:30 a.m., port spokesman Phillip Sanfield said.

The tire that blew was on a large loader that’s used to move shipping containers around the terminal, which is run by Fenix Marine Services, Sanfield said.

It wasn’t immediately clear how badly the second person was injured, but he or she was taken to Harbor-UCLA Medical Center, said Lt. Philip Heem, of the Los Angeles Port Police.

The worker who died was identified as Jose Santoyo, a 58-year-old grandfather.

Officials with ILWU Local 13 told KTLA that Santoyo died on his grandson’s first birthday. Union leaders told the station the two workers were inflating the top-handler tire, which is about 5 to 6 feet in diameter, when it exploded.

They identified the injured worker as Pedro Chavann, who suffered severe head injuries and was in a medically induced coma.

“My heart goes out to the families of the victims of this tragic accident and to all the brothers and sisters of the International Longshore and Warehouse Union,” Port of Los Angeles Executive Director Gene Seroka said in a statement. “It’s particularly tragic that this accident occurred on the day of the ILWU’s annual ‘First Blood’ event, which honors those who have lost their lives working on the waterfront.”

ILWU workers are the heartbeat of @PortofLA, and our hearts are broken by the accident that took one life today and left another seriously injured. Our thoughts are with all who love them — and we’re praying for healing and recovery for everyone touched by this tragedy. — Mayor Eric Garcetti (@MayorOfLA) May 15, 2019

Sanfield said Cal/OSHA, the U.S. Coast Guard and police were investigating. The incident was being treated as an industrial accident, according to Heem.

“Today is a tragic reminder of the danger that thousands of workers face every day working on our docks,” L.A. Councilman Joe Buscaino said. “My office will continue to work with the agencies investigating this accident.”

The Fenix Marine Services container terminal was closed for the investigation, according to port officials.

Editor’s note: This story was updated with more information from the Port of Los Angeles.