Twelve dock workers and a firefighter were injured following the leakage of flammable liquid from a container ship at the Port of Long Beach, US.

The firefighter and a worker were exposed to the fumes during the incident on Sunday morning and were subsequently taken to a hospital, reported Los Angeles Times.

Both victims suffered minor injuries and were in stable condition by Sunday afternoon, according to the Long Beach Fire Department and US Coast Guard.

The Coast Guard has identified the leaked chemical as propyl acetate, which is mainly used as a solvent.

The Long Beach Fire Department dispatched an engine company to the port's Pier G after receiving a call at around 9:30am on Sunday.

"It was found that a 6,000gal chemical tank on-board an anchored container ship spilled the hazardous substance at the terminal, which is spread across an area of 29 acres."

It was found that a 6,000gal chemical tank on-board an anchored container ship spilled the hazardous substance at the terminal, which is spread across an area of 29 acres.

A hazardous materials unit, a search-and-rescue unit and numerous paramedics were also sent to the accident site.

Two Long Beach fire boats and a lifeguard rescue boat were deployed alongside the anchored ship to establish a 1,000ft perimeter in order to protect the environment from damage.

The leak was contained and a safety zone of 150 yards was created around the ship to allow personnel to remove the chemical from the water.

Local and federal officials are currently investigating the incident and monitoring clean-up efforts, reported Associated Press.