The second explosion is believed to have been caused by the first
Three schools remain closed after two gas explosions at a former hospital in south Manchester.
A workman in his 40s suffered burns to his face, hands and back in the initial blast at the old Withington Hospital site on Tuesday morning.
A second blast followed about an hour later in the same area.
Manchester City Council said Cavendish Primary School, The Birches Special School, and Lancasterian Special School, would all be closed to pupils.
The schools' gas supply may be intermittent while investigations are carried out, but pupils are expected to return on Thursday.
Nearby properties and a police station were evacuated until the evening.
Residents returned to their homes on Tuesday evening
However, a cordon remains in place around the old hospital site, which is being turned into apartments.
The Health and Safety Executive (HSE) is to investigate the cause of the blasts but it is thought a gas main may have been damaged during building work.
Two other people suffered minor injuries as a result of the explosions.
Specialist teams from Greater Manchester Fire Service searched the area using sniffer dogs in the partially collapsed building.
But emergency services believe that all those living in properties on the site have been accounted for.
Three buildings which are in use at the hospital were evacuated, said a spokesman for the University Hospital of South Manchester NHS Foundation Trust (UHSM).
The trust cancelled all outpatient appointments for the afternoon.
Nell Lane remains closed to traffic between Princess Parkway and Elisabeth Slinger Road as the road is structurally unsafe, but residents can still get access.