Four members of a family found dead at a house in West Sussex have been named by police.
The bodies of Kelly Fitzgibbons, 40, and Robert Needham, 42, were found alongside their children Ava Needham, four, and two-year-old Lexi Needham.
A murder investigation began after police were called to Duffield Lane in Woodmancote near Chichester on Sunday.
Detectives are "not seeking anyone else in connection with the matter" and described it as an "isolated incident".
A post-mortem examination has not yet taken place and police have not commented on the nature of their deaths.
The body of a pet dog was also found at the house, police said.
Local resident and district councillor Roy Briscoe said he lived in the same lane.
"They were a young couple, with two young children. We can't believe what happened," he told BBC Radio Sussex.
"It really is saddening. The whole lane is in shock really."
Ch Supt Westerman said it was a "a very, very difficult situation to have to deal with, particularly when children are involved".
Police family liaison officers had been deployed to support the family, while detectives carry out house-to-house enquiries, speak to witnesses and carry out forensic investigations, he said.
"Importantly, we will be speaking to the family to understand what has gone on and get to the bottom of what has happened," he added.