Four homeless men have been attacked in San Diego, leaving three of them dead and the culprit remaining unknown. One man who about to be charged was released upon discovery of new evidence.

36 year-old Anthony Alexander Padgett was about to be arraigned for the crimes on Monday when new evidence led instead to his release, according to local ABC News affiliate 10 News. Padgett is homeless himself and was previously convicted of setting a sleeping transient on fire.

Victim number one, Angelo De Nardo, 53, was found burning on the morning of July 3. Video surveillance of someone buying gasoline is believed by police to reveal the killer. Authorities say Padgett’s “strong resemblance” to the man in the video contributed to his arrest. The local report cited San Diego police Capt. David Nisleit, who said that detectives still do think the man caught on tape is their murderer.

A man was seen carrying a gas can roughly two blocks away from where De Nardo was found ahead of calls to report the fire, according to the San Diego Police Department.

The day after De Nardo’s death, Shawn Longley, 41, was discovered dead in an Ocean Beach area park. Both Longley and another homeless man attacked on July 4 suffered trauma to the upper torso. Authorities believe the other July 4 attack that resulted in life-threatening injuries is related to this string of attacks.

Then, last Wednesday, a 911 call for a violent disturbance led police to 23-year-old Dionicio Vahidy, who “suffered extensive damage to his upper body,” according to the San Diego Police Department. Investigators determined Vahidy was attacked and set on fire. He was taken to the hospital, but succumbed to his injures and was pronounced dead on Sunday afternoon.

The attacks have been occurring in the early morning hours, according to San Diego Crime Stoppers, a local law enforcement initiative.

Padgett was arrested on July 7, the day after Vahidy was attacked. He was released from prison on Monday, July 11 after discovery of exculpatory evidence. 10 News cited San Diego Police Capt. David Nisleit, who said that should new evidence come to light, the focus could point to Padgett or someone new.

A $1,000 reward has been offered for information leading to an arrest.

Follow Michelle Moons on Twitter @MichelleDiana