A series of explosions on a barge at a commercial shipyard on Staten Island on Friday afternoon killed one person and injured 34 firefighters and emergency medical workers. The explosions led to a fire that was under control, but continued to burn on Friday night, said Mayor Zohran Mamdani.

The first explosion happened on a barge at 3:25 p.m. in the Arlington neighborhood, along the North Shore of Staten Island, said Brad Weekes, a spokesman with the Police Department. Firefighters responded to find heavy smoke at the scene and reports of two workers trapped inside the barge, said Lillian Bonsignore, the fire commissioner, at a news conference with Mr. Mamdani.

The firefighters called for backup. Soon after the additional personnel arrived, at 4:19 p.m., the barge erupted in a second explosion, Ms. Bonsignore said. Firefighters were inside the barge, on top of it and adjacent to it at the time of the second blast, fighting the fire and searching for the missing workers, said John Esposito, the chief of department for the Fire Department.

It was unclear when and how the person who died was killed. But they were not a firefighter, according to authorities.

According to the Fire Department, more than 200 emergency workers responded to the scene. In all, 34 members of the Fire Department were injured, said Ian Swords, a deputy assistant chief in the Fire Department. One, a fire marshal, was in serious condition at Staten Island University Hospital, where he was intubated with a brain injury and a head fracture, said Dr. David J. Prezant, the Fire Department’s chief medical officer.

Another firefighter was also taken to the hospital in serious condition, Dr. Prezant said, but by Friday evening he was recovering well. Both were injured by an intense wave of energy from the explosion, Dr. Prezant said.