Police have arrested a 34-year-old man and a 29-year-old woman in connection with a house fire in Derby in which six children were killed.
Jade Philpott, 10, and her brothers Duwayne, 13, John, nine, Jack, eight, Jesse, six, and five-year-old Jayden died in the blaze at their home in Allenton, Derby, on 11 May.
The children's parents, Mick and Mairead Philpott, 55 and 31 respectively, are in custody charged with their murder.
Derbyshire Police said that petrol was used to start the fire.
A 45-year-old man was arrested on 20 June in connection with the fire and released on bail.
Assistant Chief Constable Steve Cotterill said: "These latest arrests are part of the ongoing investigation into the circumstances surrounding the fire. Despite the fact that two people have already been charged with murder, we are continuing our investigation to ensure that all lines of inquiry are completed.
"No further information will be released at this time."
The funeral of the six children was held at St Mary's Catholic Church in Derby and followed by a private family burial at a cemetery in Chaddesden.
The parents did not attend and remained in custody.