Police on both sides of the border were continuing to seek a notorious batterer of women today as the hunt for the killer of a young Londonderry mother was stepped up.

As pregnant mother of four Jean Quigley was laid to rest today, detectives probing her vicious murder last night revisited the scene at her home in Cornshell Fields — exactly a week since she was last seen alive.

As stunned relatives were preparing for the funeral of the 30-year-old mum, whose death was described by detectives as “horrendous”, the PSNI still wanted to talk to Stephen Cahoon, who is believed to have befriended her.

Cahoon was jailed in 1999 for beating teenager Lynn McGall two years earlier.

Lynn, from Ballymena, was left for dead by Cahoon, from Moneymore, whose three-year sentence was increased to five after a campaign by the Sunday Life. He admitted 15 charges against two women — one of whom was Lynn.

He was also convicted of beating his partner Samantha Brown and threatening to kill her.

Neighbours of Ms Quigley last night said they knew little about him, but that they knew Ms Quigley had been seeing someone they thought was living in Belfast, and that police wanted to speak to him.

They also said speculation had swept the estate shortly after the murder that the man police wanted to speak to had been responsible for violent assaults on women some years ago.

While sources said that Cahoon is the man police want to talk to, the PSNI has refused to confirm it, saying the speculation is unhelpful.

Last night detectives returned to the scene of the murder, to the semi-detached Cornshell Fields house where Ms Quigley’s battered body was found last Saturday evening by relatives.

Officers handed out leaflets and talked to people in the area in an effort to gather further information regarding the circumstances of her death.

A PSNI spokesman said: “The investigation is progressing and police continue to follow a number of definite lines of enquiry.”

Police earlier this week released CCTV of Ms Quigley as she bought a pizza before returning home.

It also emerged that Ms Quigley — who told friends she was living in fear — was planning to get a new house closer to her mother when she was brutally beaten to death.

A neighbour said yesterday that everyone was still in shock, especially as they realised “how much fear she was living with”.

“Whoever did this must have known she was there alone,” said the neighbour.

Another said she was aware of speculation that Ms Quigley had known Cahoon, and that he was the man police want to speak to.

Meanwhile, some neighbours have launched a fund to help the murdered woman’s four children, aged from five to 12.

Alice Smart, one of the organisers of three vigils this week along with Marie Higgins, said: “It seems like he wrecked all of the children’s toys. Everything was smashed.

“It breaks my heart and we have started a fund to help the children.

“They are starting from scratch. We all feel for the family. ”

She added that there was still a feeling of fear in the estate:

“The killer is still out there, and that’s unsettling.”

Mrs Smart also said many residents of Cornshell Fields were preparing to join those in Galliagh for this morning’s funeral service at St Joseph’s Church.

Community worker for the greater Galliagh area Ollie Green said that there was widespread fear that whoever carried out the attack on Ms Quigley was still at large.