A serial killer is believed to be responsible for stabbing to death three homeless men in Southern California.
Police fear the attacker, who is aged between 18 and 25, is pursuing a vendetta against middle-aged men who live on the street.
His first victim, 53-year-old James Patrick McGillivray, had been sleeping rough in recent months in a shopping mall in the city of Placentia.
Police released CCTV footage of the suspect, who was dressed in black, appearing to "lie in wait" for Mr McGillivray at the mall before he attacked him on 21 December. His mutilated body was later found by a passerby. The body of the second victim, 42-year-old Lloyd Middaugh, was found near to a cycle trail in Anaheim a week later. His third victim, 57-year-old Paulus Smit, was found in a stairwell near a public library in Yorba Linda on 30 December.
All of the men were believed to have been sleeping at the time they were attacked. Police told reporters they did not know if the suspect had befriended them. An officer said: "We are concerned he will strike again."
The murders prompted comparisons to two serial killers who also preyed on the homeless in Southern California. Vaughn Greenwood, the "Skid Row Slasher", killed 11 men before he was caught in 1975. Bobby Joe Maxwell killed 10 men in 1978.