The Office of the Ontario Fire Marshal will conduct an investigation after a massive fire at a Hamilton residence that left three people suffering from smoke inhalation.

Hamilton Fire says that the blaze broke out at an address on Wellington Street South at around midnight.

They say that crews conducted an “aggressive interior attack” and were eventually able to get the fire under control.

Four dogs were rescued but one died in the blaze, Hamilton Fire said.

Three people also sustained smoke inhalation. Two of those people were treated on scene while the third was taken to hospital in stable condition.

The cause of the fire remains unknown.