One person is in critical condition in a Halifax hospital after suffering burns in a suspected propane explosion at a Dartmouth car dealership late Thursday afternoon, said Paul Maynard of Emergency Health Services Nova Scotia.

A second person is also in hospital with less serious injuries. Four other people were assessed at the scene of the explosion at O'Regan's Kia dealership on Wyse Road, said Maynard. Four ambulances and nine paramedics were on the scene.

Paramedics also examined 15 people who were exposed to fumes from the explosion.

Firefighters have put out the blaze.

A man who lives near the dealership said he heard a low whooshing sound, and then saw thick black smoke billow out of the building. Witnesses said there was a series of smaller explosions after the initial explosion.

Christine Krochak, who was behind the dealership at the time of the explosion, told CBC News she saw what she described as a badly-burned man with very little clothing and black from head to toe emerge from the building right after the explosion.

Emergency personnel got the call just before 4 p.m. local time.

Halifax fire spokesman Mike LeRue wouldn't confirm that propane caused the explosion.

Halifax Regional Police and firefighters have cordoned off the area.