Four people were arrested last night in connection with an arson attack on a family home, which left seven people dead, including five young sisters, police said.

They were being detained at Huddersfield police station following the blaze, which broke out during the early hours of yesterday in the town's Birkby district.

A West Yorkshire Police spokesman said he had no further details about the arrests but added that the bodies had now been removed from the terraced house.

The sisters, who were aged between six months and 13 years, perished alongside two adults in the fire at the house, which is owned by an Asian family.

Four people managed to escape, two by jumping through a window. Two adults remain critically ill in hospital.

Detective Superintendent Bob Bridgestock, of West Yorkshire Police, who is leading the investigation, said the incident was being treated as murder.

It is understood the house was owned by a former Muslim priest aged in his 60s.

Neighbours said he had four sons and two daughters and, at the time of the fire, one of his daughters was visiting with her children from Pakistan.

The terraced house was badly damaged in the blaze, and black marks could be seen around all the windows and front door. Police and forensic officers were were trying to establish if an accelerant had been used.

Det Supt Bridgestock said the family was well respected and well liked in the area and there was no clear motive for the attack.

Neighbours said rescuers were beaten back by the smoke and flames. Local taxi driver Mohammad Akhtar said: "The fire was so hot, it was coming through the windows and through the roof. We couldn't get anywhere near."