A man and a woman arrested by police over the deaths of five children in a house fire in Derby have been released without charge, said Derbyshire Police.
The 28-year-old woman and 38-year-old man, both from Derby, were arrested yesterday by officers investigating the deaths of 10-year-old Jade Philpott and her siblings John, nine, Jack, seven, Jessie, six, and five-year-old Jayden.
Assistant Chief Constable Steve Cotterill said: "This is a complex inquiry which requires careful and methodical investigation.
"We are still treating the fire as suspicious and are pursuing a number of lines of inquiry."
The children died after a fire ripped through their home in Victory Road, Allenton, Derby, in the early hours of yesterday.
Their 13-year-old brother Duwayne, who was also in house at the time of the blaze, remains in a critical condition in hospital in Birmingham.
A special church service is being held today in memory of the children who died.
The children's father, Mick Philpott, who was dubbed "Shameless Mick" in 2007 for his benefit claims and refusal to get a job, in a documentary by former Conservative MP Ann Widdecombe, made a "valiant" attempt to save them, police said.
St George's Roman Catholic Church, where Philpott and his family had been members of the congregation, will hold a special mass service today as well as other services across the weekend in memory of the children and to say prayers for them.
The church is affiliated with St George's Catholic Primary School, in Littleover, where the five children who died in the fire had all attended.
The children died after a fire broke out at their pebble-dashed home in Victory Road.
Philpott, said to be the father of 17 children, hit the headlines after demanding a larger house to share with his wife, Mairead, girlfriend, Lisa, and eight children.
Post-mortem examinations will be carried out this weekend and forensic specialists are examining the house.
Widdecombe, who spent a week living with the then 57-year-old Philpott for the programme Ann Widdecombe Versus The Benefit Culture, said following the tragedy: "Nobody would ever call him a bad father. I'm so sorry to hear the news and my thoughts are with the family."
Philpott is reported to have demanded the bigger property because his council house was too cramped to accommodate the family. He wanted the city council to rehouse them, but the authority said they already had the biggest available council property in the city.
Temporary Assistant Chief Constable Steve Cotterill, from Derbyshire Police, said at a press conference: "There appears to have been valiant attempts by the father to rescue his children."