According to Baltimore City Fire, crews responded to reports of an explosion on a commercial vessel near the Key Bridge site Monday.
They saw evidence of a fire and explosion when they arrived at the scene of the W-Sapphire 751-foot bulk carrier.
All 23 people aboard the carrier were accounted for and uninjured.
Authorities say this is a unified incident involving the ships owner, the Baltimore City Fire Department, the Port of Baltimore, and the United States Coast Guard.
Fireboats remain on scene as the Coast Guard and other agencies begin their investigation.
The W-Sapphire will be moved to a designated anchorage area and held there until cleared by the Coast Guard.
The BCFD operates the regions only full-time fireboat capable of responding to not only fires but also any maritime