London police are investigating a pair of early morning fires.

Emergency crews were first called to a vacant home on Calgary Street, just before three this morning. The flames were put out quickly. There's no word yet on a cause, but damage is estimated at $100,000.

Then at 5:30 this morning crews responded to a call at a townhouse on Huron Street. A man was pulled from the burning building, and CTV has been told he's a 24-year-old Fanshawe College student.
 
He was airlifted to a Hamilton hospital where he remains in critical condition.

“The occupants were woken to the sound of the smoke alarm, and at that point they tried to notify the other tenant who was in another bedroom. He was not able to be aroused,” said London Fire Department Inspector Frank Galera.

It's not yet known what caused this fire. Damage is estimated at $100,000.