A 35-year-old man who was arrested in December for killing his mother and stepfather is accused of killing seven other people around the Valley.

ABC15 has learned Cleophus Cooksey is accused of killing nine people in a three-week period in late 2017.

FULL COVERAGE: Cooksey murders investigation, timeline

Cooksey was arrested on December 17, after his mother and stepfather were found shot to death in an apartment near 12th Street and Highland Avenue. They were identified as Rene Cooksey and Edward Nunn.

The other homicides spanned across the Valley for three weeks before that incident.

The homicides happened at the following locations:

November 27

1551 E. Indian School Road, Phoenix

Andrew Remillard and Parker Smith were killed at 10:45 p.m. One victim was found inside of a black vehicle in a parking lot. A second victim was found outside of the car.

December 2

4030 N. 44th Avenue, Phoenix

Salim Richards was killed at 7:44 p.m. He was found by police critically wounded by gunfire and was pronounced dead at the scene. Officials discovered that property including a handgun had been stolen from the victim.

December 11

500 E. Harrison Drive, Avondale

Police say Jesus Real was found dead inside a home around 3:30 p.m. Three women have since been arrested for tampering with evidence in connection with this case.

December 13

5038 N. 55th Avenue, Glendale

Officers responded to an apartment complex after reports of a shooting at 6:53 p.m. Latorrie Beckford was found dead from multiple gunshot wounds along a sidewalk at the complex.

December 15

5045 N. 58th Avenue, Glendale

Kristopher Cameron was killed at 7:22 p.m. He died a day after he was found with several gunshot wounds.

December 15

1714 S. 3rd Street, Phoenix

Maria Villanueva was kidnapped at 58th Avenue and Camelback at 8:52 p.m. Her body was found on December 16 at 1714 S. 3rd Street.

Police say the investigation started when a Phoenix officer noticed something suspicious while first responding to a call about Cooksey and took the right steps.

Phoenix police Chief Jeri Williams said ballistic evidence collected from each homicide scene tied Cooksey to all homicides.

Court records show Cooksey had a previous criminal record for armed robbery and manslaughter 16 years ago. He was released from prison about a year ago and was in and out of jail since.

On Thursday, detectives added seven additional counts of homicide, seven counts of prohibited possessor of a firearm, one count of sexually motivated kidnapping, one count of firearm theft, and one count of armed robbery with a deadly weapon.

If you have any information about any of these crimes call Avondale police, Glendale police or Phoenix police. You can also call Silent Witness at 480-WITNESS.