Three men have been found dead after reports of a fight in Colchester.
Essex Police said a 32-year-old man was being questioned on suspicion of murder over the deaths on Saturday night.
Two men were discovered at a property on Wellesley Road and a third was found in a car outside.
Officers, who were called to the scene at about 22:15 BST, said they were "keeping an open mind" about the circumstances.
The force urged anyone in the area between 18:00 BST on Saturday and 01:00 on Sunday who saw anything suspicion or unusual to contact them.
David Beales, 64, an Anglican minister who lives on the street opposite the property affected, said he "heard nothing" overnight and woke up to find police officers walking up and down the road.
"This is normally quite a peaceful street," he said, adding: "There has been a history of sometimes noise in the flats where the incident took place, but nothing dire like this."