About 60 firefighters descended on the home in a residential area and brought the children out as intense fire ripped through the building Thursday night.
The youngsters were treated at the scene and taken to a hospital, where they were pronounced dead. The children—two sets of twins ages 3 and 4—are believed to be related.
“This is an incident that has left everyone numb with profound sadness,’’ London Fire Commissioner Andy Roe said. “My thoughts are with the family and friends of the children, the whole local community and all those who will be affected by this fire.’’
Roe said the firefighters were being offered counseling as a priority. The cause of the blaze is under investigation.