Winnipeg police confirmed Tuesday that a fire that tore through the new Grace Hospital emergency department is being investigated as arson.

Police said they spotted a suspect at around 4 a.m. Tuesday morning near Sturgeon Road and Ness Avenue.

An 11-year-old boy was taken into custody in connection to the fire, but he has since been released to his guardian.

He cannot be charged because he is under the age of 12.

The blazed started shortly before 11 p.m. Fire crews responded to flames coming from the roof of a vacant building on the hospital’s property. Police said the fire did not impact hospital operations.

Rob Kerr lives in the area, and told CTV New he called 911 after seeing a fire across the street around 10:40 p.m. Monday.

“Looked out the window, and there was just this big, orange flame starting to come up off the roof of the new emergency ward they’re building at Grace Hospital,” Kerr said.

Kerr said it appeared to be the part of the site closest to Booth Drive.

"Luckily the new construction was far enough away from the hospital,” Kerr said.

“From where I stood I couldn't see any activity at the hospital itself. I'm not sure."

Kerr said it looked like firefighers had to cut through construction fencing to get to the blaze, and that it took crews about five minutes to get the fire under control.

Fire officials confirmed that crews did respond to a fire at a vacant building under construction on the north side of the hospital.

Officials also said the fire appeared to have mainly damaged the roof of the vacant building. There was no fire or smoke damage to the hospital.

They said water supply access was slightly hindered because one hydrant that was inoperable.

Police said that no injuries were reported, and that all roadways are now open.