Two Irish American security workers were found dead in mysterious circumstances on the Maersk Alabama, the ship made famous by the Tom Hanks movie "Captain Phillips" in 2013, after an apparent heroin overdose.

Seychelles police identified the bodies found as Jeffrey Reynolds and Mark Kennedy, both 44. They worked for Trident Group, a Virginia-based maritime security services firm, and Trident Group President Tom Rothrauff said both were former Navy SEALs.

A spokesperson for the US State Department, Marie Harf said, “American agencies are investigating.

“This incident is currently being investigated by the U.S Coast Guard in part because of the US flag vessel.”

The Maersk Alabama was made famous in 2009 when pirates hijacked the ship holding the crew hostage. Last year the crew’s ordeal was turned into a blockbuster movie with Tom Hanks taking the lead in "Captain Phillips."

The hijacking ended after navy seals shot and killed three of the pirates holding the captain hostage.

The men found dead on board the ship are believed to not have died as a result of “vessel operations on their duties as security personnel.”

The company's president, Tom Rothrauff, confirmed to CNN the men were former Navy SEALs.

'It's bizarre. Of course, it's a shock. They're all great guys,' Rothrauff said. 'I'm absolutely clueless as to what happened.'

Mark Kennedy was married to Julia and had a son. He lived in Baton Rouge, LA.

Kevin N. Speers, a senior director for Maersk Line, said in a statement the deaths of the two men were "'not related to vessel operations or their duties as security personnel."

The Maersk Alabama is a Norfolk, VA-based container ship that provides feeder service to the east coast of Africa and employs security contractors to provide anti-piracy services.

The Navy confirmed that Kennedy belonged to the SEALs, an elite unit of the Navy's special operations forces who are sometimes called upon to combat piracy.

Officials say they found needles and heroin inside the cabin where the two ex-special forces navy men were bunking.

According to CNN, a government official, who spoke on condition of anonymity, said the presence of drug traces and paraphernalia "would suggest that their deaths were a result of drug overdose."

The New York Times reports that on the night before their lifeless bodies were found, Jeffrey Reynolds and Mark Kennedy enjoyed the nightlife in the Seychelles capital.

The two men later visited two casinos, playing blackjack and drinking vodka and tequila with sailors from New Zealand.

“When the second casino shut its doors at 3 a.m., surveillance images show that the pair bumped into two women and departed with them down a dark corridor.”

It was in Mr. Kennedy’s cabin, more than 12 hours later, that a ship security officer discovered the two men on Feb. 18.

Mr. Reynolds was slumped on the bed, and Mr. Kennedy was lying face up on the floor, a syringe in his left hand, brown heroin powder in the room, according to police reports. It was unclear how long they had been dead.