One man was killed Thursday evening after the speedboat he was driving capsized on the Mississippi River in Champlin, according to the Hennepin County Sheriff’s Office.

Rescuers were dispatched to Mississippi Point Park around 4 p.m. on a report of a person in the water. The victim was pulled to shore and declared dead at the scene. He was the lone occupant of the boat.

It remains unclear what caused it to overturn.

The Hennepin County medical examiner’s office will release the identity of the victim, along with his cause of death, once the family has been notified.

The incident is under investigation.