One person was taken to hospital with minor injuries after an early morning house fire in south London.

Emergency crews were called to the blaze on Millbank Drive near Wellington Road and Southdale Road just after 4:15 a.m.

"When we arrived on scene, we had three vehicles in the driveway that were fully involved, and the fire was working its way up the outside of the building, into the attic and appeared to be venting out through the roof," said London Fire Department district chief Dave Hood.

"The fire was very difficult, there was a fair amount of debris that's been stored through the house, so it was very difficult to get to the seed of the fire. It turned into a defensive fire that we had to attack with the aerial ladder."

Three vehicles in the driveway also caught fire (Kate Dubinski/CBC London)

Two occupants of the home were already outside when firefighters arrived and one of them was taken to hospital, Hood said.

He said the amount of debris inside the home, likely caused by hoarding, made fire crews' job more dangerous and difficult.

"Some of the rooms were inaccessible. If we had to go in to get someone out, that would have been very difficult."

The cause of the fire is not yet known.