Officers have arrested a fourth man in connection with a house fire in Bentilee last week.
Police were called to a property on Beverley Drive, at about 10.55pm on Thursday (16 December).
A 31-year-old woman and a 13-year-old girl remain in a critical but stable condition in hospital following the fire.
An 18-year-old man from the Stoke-on-Trent area was arrested at Manchester Airport on Wednesday (22 December) on suspicion of attempted murder.
He has since been released on conditional police bail.
Three other men from Stoke-on-Trent: a 28-year-old, arrested on suspicion of wounding; a 22-year-old and a 21-year-old both arrested on suspicion of attempted murder, are all currently on conditional police bail.