A murder investigation has been launched following the deaths of two women outside a property in Crawley Down.
On Sunday, police were called to the address just after 10am where they also found a man seriously injured inside. He was taken by ambulance to the Royal Sussex County Hospital, Brighton.
A man has been arrested on suspicion of murder.
Detective Chief Inspector Alex Geldart, of the Sussex and Surrey major crime team, is leading an investigation into the incident.
She said: “At this time we believe this to be an isolated incident, with no ongoing risk to members of the public.
“This is a fast-moving investigation which will see significant police resources deployed to the scene for the forseeable future. We are grateful for the support and patience of the local community while we conduct our enquiries.“
DCI Geldart added: ” My thoughts are very much with the friends and family of the two women who have sadly lost their lives.”
The Mail Online reported that the incident took place after a man allegedly armed with a knife carried out the attack just days before Christmas.
According to reports, he was detained by police once officers arrived at the scene.