Investigators are examining how a blaze which ripped through a tower block killing six people, including a three-week-old baby girl, was able to spread so quickly, officials said.
Doubts were raised over whether escape routes and fire prevention measures were adequate at the 12-storey 1960s building, which had a single central staircase.
Fire officials said a "unique situation" caused "one of the most significant fires in some time".
Helen Udoaka, 34, and her three-week old daughter Michelle, were among those killed in the fire at Lakanal House in Camberwell, south London, on Friday night.
Dayana Francisquini, 26, and Filipe Francisquini, three, also died, along with Catherine Hickman, 31.
The sixth victim, who has not yet been identified, is believed to be a four-year-old girl, police said.
Harriet Harman, the area's MP, said people were "asking questions" about fire escape routes in the tower block.
"There will have to be a thorough investigation in to what caused this fire and whether the prevention was adequate," she said.
Several residents described the complicated layout of the maisonettes as "a maze" and said it made the evacuation difficult while onlookers described seeing those trapped inside screaming for help.
The cause of the fire, which is believed to have started on the ninth floor, has not yet been established and officers are treating it as suspicious, police said.
Read More
MORE ABOUT