Windsor firefighters and police were on scene at a fire on Mercer Street Saturday morning that left one person with second-degree burns.

A couple who lived in the duplex where the blaze struck say they woke up to heavy smoke in the house but were able to escape.

A fire official says at least three people were able to leave the home safely, while a man had burns to 10 per cent of his body, including his face and hands. He is expected to be released from hospital soon.

It appears the fire originated in the back of a unit in the 700 block of Mercer.

"The one unit is pretty extensively damaged. We're calling it about $175,000. The adjacent unit...has some minor smoke damage to the upstairs but no fire damage or water damage," says John Lee, Windsor's chief Fire Prevention Officer. 

Police say a 60-year-old man has been arrested.

Among the evidence officers cleared from the building was a damaged red jerry can. It was taken away in a transparent bag.

Lee says investigators continue to look at evidence.

"We've taken some samples. We want to take a look at some of the evidence that we've taken from the scene and look at it more thoroughly," he says.

Windsor firefighters were also at a downtown apartment building late Friday night.

The blaze at Le Goyeau apartments at the corner of Riverside Drive and Goyeau Sreet was called in just before midnight.

The building had to be evacuated and fire officials say the blaze started on a sixth floor balcony.

One tenant was displaced but there are no injuries. Damage is pegged at $30,000.

A fire inspector is investigating.