(CNN)A boat that had 21 occupants on board exploded on Thursday in Fort Lauderdale, Florida, injuring a total of 13 people, authorities said.
Fort Lauderdale Fire Rescue received several emergency calls for a boat that had exploded on the New River in Fort Lauderdale this afternoon, said Fort Lauderdale Fire Rescue Battalion Chief Stephen Golan.
There were a series of explosions, and authorities said they are unsure of the cause.
The 13 individuals harmed in boat fire received burns from first to third degree, according to police. Seven patients were transported to Broward Health, including one in stable and two in critical condition.
A patient in serious condition was expected to be transferred to another medical facility, while the last five individuals were transported with minor injuries, Golan said.
At the time of the incident, the boat was outbound on the New River headed toward the intercoastal, Golan said. The boat was a 41-foot Wellcraft, but it is unclear whether it was private or charter.
"The scene was challenging at the start, due to the boat being on the north side of the river and all the patients being on the south side of the river," Golan said.
"So our crews immediately divided, with a fire attack on the north side of the river, stopping the boat from floating down the river any further, while our rescue crews were on the south side of the river, at the Lauderdale Marine Center, treating patients."
The Fort Lauderdale Fire Department said it will be working on an investigation to see what caused the boat fire.