Two women have been found dead and a man seriously hurt at a house in West Sussex.
The victims’ bodies were discovered outside the property in Hazel Way, Crawley Down, while the man was found inside.
Detectives have arrested another man on suspicion of murder.
Earlier reports suggested a knife had been involved in the attack, but Sussex Police have since said “this is not a knife crime”.
The force gave no further details about the arrested man or the cause of death. The injured man has been taken to Royal Sussex County Hospital in Brighton.
Det Ch Insp Alex Geldart said: “This is a fast-moving investigation which will see significant police resources deployed to the scene for the foreseeable future. We are grateful for the support and patience of the local community while we conduct our inquiries.
“My thoughts are very much with the friends and family of the two women who have sadly lost their lives.”
The detective said it was an isolated attack with no risk to the public and added: “In response to media speculation I wish to make it absolutely clear that this is not a knife crime.”
Three forensic tents were pitched in the street and investigators in white forensic suits could be seen combing the area for evidence.
A police cordon remains in place around the houses close to where the bodies were found.