Two men have been charged with two counts of murder and 14 of attempted murder in Phoenix, a US city terrorised by a series of killings.
Dale Hausner says he is innocent
Dale Hausner, 33, and Samuel Dieteman, 31, have also been charged with 16 counts of drive-by shooting.
"These alleged crimes have caused carnage and terror in our community," County Attorney Andrew P Thomas said.
Another man who is still at large and has been dubbed the "Baseline Killer" is blamed for eight other murders.
Mr Hausner and Mr Dieteman are suspected of being behind the so-called "Serial Shooter" case.
Sixteen attacks have been blamed on the "Serial Shooter".
The two men, who are friends, were arrested last week at a gated apartment complex in Mesa, Arizona, less than three miles (5km) from where a 22-year-old woman was killed.
On Monday, Mr Hausner said in an interview from the jailhouse that he was innocent.
Officials have said the random nature of the murders has made investigations difficult.
Fear gripped the Phoenix area in recent months as police linked more and more seemingly random shootings, raising fears that two separate serial killers were competing with one another to see who could take the most lives.
The "Baseline Killer", blamed for a cluster of murders, armed robberies and sex attacks, was given the name after the Baseline Road area of the city, where many of the attacks have taken place.