Authorities in Arizona have recovered bullet casings from at least three of the crime scenes believed to be linked to a serial killer behind nine nighttime drive-by shootings in Phoenix.
They have also received detailed vehicle descriptions from witnesses, according to police reports.
Witnesses say the victims were standing outside after dark when a man fired a handgun from a car and then fled the area. Police say the documents were released Tuesday in response to public records requests from news organizations.
In all, seven people have been killed and two others wounded in shootings from mid-March until mid-July. The attacks are occurring in two predominantly Latino neighborhoods located about 10 miles apart.
Investigators believe the crimes were carried out by a lanky Hispanic man in his early 20s, but they are leaving open the possibility that someone else may have participated in the attacks. They don't believe the attacks are racially motivated. No motive has been established.
Though the reports specified that shell casings were found at each of the three crime scenes, investigators declined to reveal whether that evidence or other evidence led them to conclude the attacks are related and committed by the same killer.
"I am confident they are linked," Phoenix police spokesman Sgt. Jonathan Howard said.
In the first attack on March 17, witnesses said a young man driving a late '90s brown Nissan car with tinted windows and a rear spoiler pulled up to a 16-year-old boy who was outside with friends, extended a handgun out of the car's window and shot the victim in the arm, stomach and hip. The victim saw only part of the suspect's face.
Two weeks later, police say the same suspect shot Diego Verdugo-Sanchez, 21, after the victim left his girlfriend's mother house to go outside and lock his SUV. The make of the shooter's vehicle was redacted from that police report but a witness saw the vehicle speeding away after the shooting and said a person was seen in the backseat with a hand out the car's right rear window.
The family of Verdugo-Sanchez's girlfriend found him in the street bleeding. His then-pregnant girlfriend held his hand until officers arrived at the scene.
And on April 19, a witness reported seeing a car stop near the area where the body of 55-year-old Krystal Annette White was found in a patch of gravel. The witness was awakened by the sound of gunshots and saw a man get into the car and leave, according to the police report.
Police have appealed to the public for tips to help them catch the killer and a $50,000 reward has been offered for information leading to an arrest.
The last Phoenix serial killing case was in 2005-2006 when six people were killed and 19 wounded in a series of seemingly random shootings. Two men were convicted.
Based on reporting by The Associated Press.