Sioux Falls police are investigating after an injured man was dropped off at a hospital in a plastic tub.

A police spokesman says the 18-year-old Sioux Falls man was dropped off at an emergency room Tuesday afternoon. The driver left after dropping the man off at the hospital.

The victim suffered life-threatening injuries, including skull injuries. The police spokesman did not know how the man was injured.

Police were able to identify the man who dropped off the victim at the hospital through the victim’s family members, along with other people who may be involved.