A man died early Thursday morning after going into cardiac arrest during a house fire in St. Paul that displaced four others.

According to the St. Paul Fire Department, crews arrived to the single family home on the 400 block of Cook Avenue East around 12:45 a.m. They found heavy fire conditions and entered the building, where they were quickly able to bring the flames under control.

Crews found a man on the second floor, who was taken to the hospital in cardiac arrest. He was pronounced dead at the hospital shortly after, the fire department says.

Officials say that a preliminary investigation found a space heater near the area where the fire started.

The victim's identity will be released by the Ramsey County Medical Examiner's Office. The Red Cross is helping the four other people — three men and one woman — who were displaced by the fire.

The fire department says that the man's death cannot be ruled a fire fatality until investigations are complete. The city averages less than three fire fatalities a year, but has seen five fire fatalities in 2025, the department says.