A suspected boat explosion at a Miami sandbar sent at least 11 people to the hospital on Saturday with some suffering from burns and traumatic injuries, according to Juan Arias, the Miami Dade fire rescue battalion chief.

First responders received reports roughly around 12.45pm of a possible boat explosion on the water, Arias told WPEC 12.

It is unclear what caused the blast, which occurred onboard a charter boat with about 14 people, according to NBC 6 South Florida.

The Florida fish and wildlife conservation commission is investigating the incident, according to the Associated Press.

The Haulover Sandbar beckons hundreds of spring breakers and other vacation-oriented visitors every year. Located in shallow waters, the sandbar has been a boating mecca. Kayakers also regularly descend upon the strip.

Patrick Lee, a local businessman, was driving people onboard his boat to another vessel on the water during the blast, he told the Miami Herald.

“When we looked back out, we saw three people flying off the boat in a puff of smoke,” Lee said.