It follows the death of 47-year-old Philip Ellison who was stabbed to death during a visit to a supported housing scheme which helps people recover from mental health problems.

A 51-year-old, who was arrested at the scene of the stabbing in Glebe Close, Fulwood, has been detained in secure accommodation under the Mental Health Act. Glebe Cottages is owned by the Places for People group.

Ribble Valley MP Nigel Evans, whose constituency covers Fulwood, said: "There has got to be a full inquiry. Lessons have to be learned to protect other social workers."

Coun Chris Cheetham, cabinet member for adult and community services at Lancashire County Council, said: "We will have a full and thorough investigation with our partners from Lancashire Care NHS Trust.

"The police will hold a criminal investigation and ours is going to be looking at the circumstances of what happened."

Mr Cheetham said the investigation would probably begin immediately.

He added: "We want to quickly see if there are any lessons that need to be learned."

Meanwhile, residents in Glebe Close, just yards from Fulwood Tennis Club and close to the local police station, said the stabbing raised concerns.

Pensioner Sheila Trafford, 62, said: "There are similar cases up and down Britain involving people with mental health issues.

"The powers that be don't take any notice of the concerns of the public. But we have to live here. There are a lot of children around here. What has happened raises many questions.

"You see people coming and going and you can tell some of them have difficulties – you just keep your head down."

Mum-of-two Shelley Pennington, 23, said: "I just want to know what kind of people are living on our doorstep.

"They keep themselves to themselves. We knew there were people living here who needed help but did not realise to what extent.

"I have two children aged four and two and this has made me worried."

Other residents have defended the community.

Diane Ewart, 37, said: "The people who need care have been here longer than some of the other residents and have never caused any trouble."

>> Tributes paid to social worker killed on duty

>> Knife death arrest captured on phone

>> Murder suspect detained in secure unit

>> Social worker stabbed to death was father-of-three

>> See footage from the crime scene

>> Murder probe after social worker stabbed to death

>> Residents shocked at death on 'quiet' street (with video)

>> Cordon goes up around scene of suspected murder

See Tuesday's Lancashire Evening Post for more coverage of this story.

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