Heath Barnes opened his book on the upper decks of the Bahamas-bound Carnival Freedom cruise ship in between bouts of rain.

But his relaxation Saturday afternoon was suddenly stolen with “the loudest thunder and lightning I have ever heard,” he told CNN.

Barnes, of Woodsboro, Maryland, went back inside and minutes later learned from his nephew and his nephew’s two friends, all 16, the ship was on fire.

“I thought they were giving me a hard time, but I got up and went out on the balcony and sure enough, the flames and smoke was pouring out of the tail,” said Barnes, who shared footage of the incident with CNN.

Cruise ship officials reported the fire broke out on the port side of the ship’s exhaust funnel around 3:15 p.m. local time, according to a news release from Carnival Cruise Line.

Witnesses reported the ship may have been struck by lightning, but that has not been confirmed and the cause is still being investigated, according to the cruise line.

As the ship’s fire response team worked to extinguish the blaze, the cruise’s captain turned the ship toward an area of heavy rain to help put out the flames, the release states.

The fire appeared to be extinguished about two hours after it ignited. There were no reported injuries to guests, but two firefighting crew members were treated for minor smoke inhalation, according to the cruise line.

The port side portion of the exhaust funnel fell onto deck 10 of the ship as a result of the fire, according to Carnival.

The ship was about 20 miles off Eleuthera Island, Bahamas, when the fire broke out. The blaze started as the ship headed to Freeport, the release said.

The cruise line said passengers were able to attend dinner as planned Saturday night.

The US Coast Guard has been notified about the incident.

Barnes said after the fire broke out, passengers were told to remain in their cabins until about 5:40 p.m.

This was his 18th Carnival Cruise trip.

“This was the most interesting one,” he said. “It’s not their fault, it’s Mother Nature.”

Carnival said later on Sunday it had completed a thorough assessment during the ship’s visit to Freeport and discovered the damage was worse than the cruise line initially reported.

The Carnival Freedom cruise trips originally scheduled to depart from Port Canaveral, Florida, on March 25 and March 29 have been canceled to allow “immediate repair to stabilize the funnel,” the cruise line said in a news release.

“The funnel has been stabilized for the ship’s return to Port Canaveral overnight to disembark guests, and then it will go to the Freeport shipyard on Monday afternoon to begin the required repairs,” according to the updated release.

Carnival announced full refunds and future cruise credits for passengers scheduled to depart on the canceled cruises.

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