A murder investigation has been launched after a family of four and their dog were found dead in a West Sussex village.

The bodies of a man, his partner and their two young daughters, were discovered at a house in Woodmancote, near Chichester.

Sussex police named them as Robert Needham, 42, Kelly Fitzgibbons, 40, Ava Needham, four, and two-year-old Lexi Needham.

Officers attended the property in Duffield Lane at about 6.45pm on Sunday after receiving a call raising concerns for the welfare of the residents.

When they arrived, they found four bodies. Police said they were treating the incident as a murder investigation but detectives were not looking for anyone else in connection with the deaths.

The family were seen at the end of last week taking their daily exercise in the fields around their home.

Ch Supt Jerry Westerman said: “This is believed to be an isolated incident contained to one property and in these early stages of the investigation we are not seeking anyone else in connection with the incident.”

Residents of the village were told they could expect to see a heightened police presence in the area.

Robert Needham had been building an extension for the family after moving back to his mother Maureen Needham’s home.

Robert Needham. Photograph: Sussex police

Douglas Meany, a neighbour, said he had known the Needham family for 40 years and often drove Maureen, 77, to the doctor’s surgery.

“I’ve known the family a very long time. We got on well as neighbours. As far as I know they were a fairly close-knit family, just normal, but not in each other’s pockets,” he said.

“For a while the house was used as a care home the family ran. Previous to that, Maureen and her husband used to run a village shop.

“On Sunday, I was alerted to the fact there was a lot of activity in the lane outside. I saw two paramedic vehicles, unmarked police cars in the lane as well as marked. That carried on right through the night, comings and goings, and forensics seemed to arrive at around midnight.

“As there was more police and paramedics involved, we knew that somebody was in trouble, then it came to light that there may have been fatalities and there might have been more than one.”

Two days before the incident, Kelly Fitzgibbons posted on social media pictures of Robert and her children on their “walk for the day” during the coronavirus lockdown.

Meany said: “There was no evidence previously that there was a problem. Robert was building an extension for the family to live in, but while he was building it he wasn’t getting an income from any other building work.

“I think Robert and Kelly and the children tended to stay in a section of the house and Maureen stayed in another section. Maureen has relatives in Manchester and near London and she does spend time with them. I don’t know where she is.”

On Facebook on Tuesday, Maureen said: “It was Robert, Kelly and my lovely grandchildren that all died upstairs.”

Another resident, Ian Richardson, said it was a close community and the neighbourhood was considered a low-crime area.

He added: “I have tried to put it into context and think it’s something that happens all over the place.”

A Home Office pathologist will try to determine how the family died.

Anyone with any information is asked to contact Sussex police on 101, quoting Operation Cotton.