Arizona police say they believe they've pieced together a "jigsaw puzzle" they had been struggling to solve for weeks after identifying a man they believe is responsible for the deaths of nine people.

If convicted, 35-year-old Cleophus Cooksey Jr. would become one of the most prolific serial killers in the state's history.

Cooksey was arrested on Dec. 17, 2017, for the deaths of his mother and stepfather, who were both found shot dead. While in custody, police say they linked Cooksey to seven other homicides in the Phoenix, Avondale and Glendale areas.

"To solve nine homicides in a period of three weeks is outstanding," Phoenix police Sgt. Jonathan Howard said at a press conference on Thursday. "The suspect takes steps to avoid detection...so it's not often that we have the ability to gather the evidence this quickly and do it."

Here's what we know about Cooksey and the charges he's facing so far.

Growing up

Cooksey is the grandson of well-known Arizona civil rights leader Roy L. Cooksey, who died on Aug. 12, 2009, at the age of 84.

The elder Cooksey opened the state's first black-owned daycare center in Tucson, helped form the Afro-American Coordination Committee in 1960 and was honored several times for his public service throughout his lifetime, according to a 2009 article in the Arizona Daily Star published days after his death.

Cooksey claimed he had a troubled childhood.

He told police his father abused him, resulting in his hospitalization at the age of 12, the Arizona Republic reported. By 16, Cooksey had moved out of his family home.

Rap artist?

Cooksey started rapping under the nickname "King Playbola" about two years ago at the age of 33.

A YouTube channel under his name contains nine videos of a man rapping from his couch. The page has eight subscribers.

When asked to confirm the authenticity of the YouTube videos, Howard said he had not yet seen them.

However, he said, he did have information about Cooksey being an "aspiring music star."

"So that would certainly lead me to believe that’s accurate," Howard said.

A history with the law

Cooksey served about 16 years in prison after being convicted of manslaughter in January 2001 at the age of 18, according to the Arizona Department of Corrections records.

“[He was jailed] when a man he was working with who committed an armed robbery was killed,” Howard said.

While in prison, Cooksey was found guilty of 22 infractions including assault on a staff member, unauthorized smoking, drug possession, fighting and disobeying orders on numerous occasions, records show.

He was released from prison in January 2015. Ten months later, he received a DUI.

Cooksey was arrested again in May 2016 on a "technical violation" and returned to prison, where he awaited court appearances.

He was freed in June 2016, but was arrested and booked again six months later because of an arrest warrant. He was released on community supervision on July 28, 2017. Months later, Cooksey allegedly committed a string of killings that left nine people dead.

His current status

Cooksey was arrested and charged with two counts of first degree murder on Dec. 17, 2017.

On Thursday, Howard said detectives rebooked Cooksey for an additional seven counts of first degree murder, eight counts of being a prohibited possessor, theft of a firearm, armed robbery and sexual assault.

The Maricopa County Attorney’s Office will determine the charges Cooksey will face throughout the investigation.

Police are asking the public with information about any of the crimes to notify their local authorities or contact the non-profit program Silent Witness.