A WOMAN may have been involved in the killing of a wealthy businessman during a robbery.
Police have also revealed that inquiries into the murder of 57-year-old John Luper at his north Leeds home are focusing on the Liversedge and Bradford areas.
Up to five masked people are thought to have been involved in the raid on Mr Luper's house in Sandmoor Drive, Alwoodley, in the early hours of Tuesday, February 17.
Det Supt Bill Shackleton, who is leading the inquiry, said: "Our investigations lead us to believe that one of the intruders is possibly female.
"There are at least four, if not five suspects and all wore balaclavas, dark clothes and gloves."
He added: "We still believe the answer lies within the community of West Yorkshire.
"We are not ruling out a Leeds connection, but we are focusing inquiries in the Liversedge and Bradford areas.
"This was an extremely well-planned offence and it's likely that Mr Luper and his family were targeted for their wealth, rather than for any personal reason.
"It is possible that whoever is responsible for it may have carried out similar attacks."
Mr Luper's wife, daughter and au pair discovered Mr Luper in the breakfast room next to the kitchen and called police at 1.45am.
They had freed themselves after being tied up by the intruders. Attempts were made to resuscitate Mr Luper, but he was pronounced dead at the scene.
Mr Luper was swiftly incapacitated while walking his dog about 11.30pm and dragged back to his own home with no signs of a struggle.
Tests revealed a cause of death to be asphyxiation. An inquest has been opened and adjourned.
Around £1,000 was taken, along with Mr Luper's burgundy leather wallet and Mrs Luper's purse.
Jewellery including diamond rings, earrings, a Rolex watch and two Cartier watches were also taken.
Det Supt Shackleton said: "One of the Cartier watches is particularly distinctive, featuring diamonds in the face. We believe only four watches like this were sold in the country last year."
The police number is 0113 241 3259 or people can ring Crimestoppers in confidence on 0800 555111.