(CNN) -- A voice on the intercom woke Danielle Miller and told her to put on her life jacket and run to a deck. Not knowing what the emergency was, she woke up her roommate and did just that.
The emergency, as she and other passengers would learn, was a fire that started in the rear of Royal Caribbean's Grandeur of the Seas cruise ship about 2:50 a.m. Monday while it was heading to the Bahamas, sending guests to the decks under the night sky.
Though never losing power, the ship was diverted to Freeport in the Bahamas, and the fire, which began in a mooring area, was extinguished just before 5 a.m., the company said.
The ship's 2,224 guests and 796 crew members initially were headed to CocoCay, Bahamas, but the ship was redirected to Freeport for evaluation, Royal Caribbean said.
"We probably ran up to that deck faster than we ever ran before," Miller said by phone from Freeport on Monday afternoon, a few hours after the ship docked. "We were terrified, though, and a lot of people were just crying and freaking out."
Two guests were treated after fainting, and medical staff also responded to reports of high blood pressure and an ankle sprain, Royal Caribbean said.
Royal Caribbean spokeswoman Cynthia Martinez said she didn't have further information about the medical reports, "but the ship has told us that there are no medical emergencies onboard."
The fire started on the aft mooring deck and spread to the fourth deck at the crew lounge area before it was extinguished, U.S. Coast Guard spokeswoman Marilyn Fajardo said. Information on the fire's cause wasn't available, she said.
Grandeur of the Seas departed Baltimore, Maryland, on Friday for a seven-day trip with scheduled port calls to Port Canaveral, Florida; CocoCay; and Nassau in the Bahamas, the company said. CocoCay is Royal Caribbean's "private island paradise" in the Bahamas, according to its website.
Video captured by Miller and friend Katie Coleman shows guests gathered on a deck, seemingly calm, wearing orange life jackets and listening to instructions.
"We're on deck right now, 3 a.m., in our life jackets. Not a drill, not a joke," a narrator in Miller's video says.
The ship arrived at Freeport about 10:15 a.m., Royal Caribbean said. Throughout, the power, propulsion and communications systems were uninterrupted, the company said.
"In an abundance of caution, the captain deemed it necessary to muster all guests at their assembly stations during the incident," the company said in a news release. Everyone aboard was accounted for, and guests have been allowed to return to most staterooms and public areas, it said.
Passengers will be able to get off the ship at Freeport if they choose, Martinez said. The company's president and CEO, Adam Goldstein, and other Royal Caribbean officials were heading to Freeport on Monday morning to meet guests, she said.
"NTSB joining investigation with Coast Guard into fire on Royal Carib's Grandeur of the Seas in Bahamas. No injuries," the National Transportation Safety Board said on Twitter.
Miller said she didn't know initially why guests were being gathered on deck.
"Before we went to bed, there was a pretty bad storm, and the ship was really rocking, so our first thought was that we were sinking, because they said 'life jackets' and run," Miller said. "We got up to the deck, and we see the lifeboats being lowered down. ... We didn't know what was going on for about a half-hour, when they made an announcement that there was a fire."
She said the crew handled the situation well.
"Even though it was terrifying, they tried their best to make everyone comfortable. They're so well-trained that I felt confident that we would be OK," she said.
The 916-foot-long ship was launched in December 1996 and refurbished in May 2012, the company said.
A number of cruise ship incidents have made headlines in the past year and a half.
In January 2012, 32 people died when the Costa Concordia capsized off Italy's coast.
In February this year, an engine room fire left the Carnival Triumph adrift in the Gulf of Mexico, with passengers reporting overflowing toilets and human waste running down the walls in some parts of the ship.
On a March cruise, the Carnival Dream lost power and some toilets stopped working. And this month, authorities say, a man and a woman on the Carnival Spirit fell overboard off Australia's coast; they are presumed dead.