A substantial emergency response was triggered Saturday after a Boston duck boat overturned near a Cambridge boat ramp, leaving six people injured.

The amphibious craft tipped over at a ramp that enters into the Charles River, Massachusetts State Police confirmed. 

While all passengers on board have been accounted for, the injuries ranged from mild to moderate, with two victims sustaining more serious trauma, according to the Cambridge Police Department.

In the wake of the accident, Boston Duck Tours announced a total suspension of operations for the remainder of the day. 

“As a precaution, we have suspended operations… and are working with Massachusetts State Police and the U.S. Coast Guard to review the incident,” the company said in a statement.

State troopers, the Marine Unit, and local fire crews all descended on the scene following the mishap. 

The Massachusetts State Police are currently leading the investigation into what caused the vessel to capsize.