Three children were burned, two severely, after the boat they were riding on exploded in southern Maryland on Saturday, the Washington Post reported.

The children were airlifted to D.C. Children’s Hospital after the 20-foot boat caught fire on Mill Creek in Lusby, Md., about 60 miles southeast of Washington, D.C, Maryland Natural Resources Police spokeswoman Candy Thomson told the Post.

The incident happened around 11:30 a.m., just minutes after the family had launched from the marina, Fox5DC reported.

A three-year hold and nine-year-old were being treated for severe burns at the hospital. Their eight-year-old sibling was also hospitalized.

The children’s parents were also on board.

The cause of the fire is under investigation.