For an unknown reason, the police vehicle was in reverse when it hit a barrier and flipped off a walkway in Kungsholm, central Stockholm, and into the waters of the Riddarfjärden.
The officer, who is reportedly in his mid-forties, went directly through the ice and the vehicle pressed him under the water.
Another officer jumped down to help, and together with two nearby ice-skaters managed to help pull the man to the shore.
Paramedics performed CPR and took the policeman taken to hospital, but the man passed away at 8pm on Monday.
“Our colleague unfortunately died,” Lars Byström of the Stockholm police told the TT news agency.
“It will be up to the investigation to determine how and why it happened.”
There were several witnesses in the area when the incident occurred in the early afternoon on Monday.
“I saw it, it was surreal,” Fredrik Braconier told the Expressen newspaper.
“It was the kind of thing you see in a movie, not in Kungsholms torg.”
The policeman was working together with other officers as part of a heightened security effort in conjunction with the state visit of Turkey’s President Abdullah Gül, who is in Sweden for three days.
Police have launched an investigation.
“We have talked to witnesses and taken information from them. We have photographed the area and tried to capture what happened,” Byström added.