PHOENIX - Police have identified new victims in a series of Phoenix shootings that resulted in the arrest of a 23-year-old man.

Authorities on Monday said Aaron Saucedo faces homicide charges in connection with a case police have said was the work of a serial killer.

Police previously said at least seven people were killed and two others wounded over a four-month period last year. On Monday, they raised the number of people killed to nine and said there were 12 total shootings - with the first one happening in 2015.

Police say one of the nine people was a 61-year-old man killed in August 2015 whom Saucedo knew through his mother. Authorities say Saucedo did not know the other victims.

Saucedo initially was arrested last month in connection with the August 2015 killing. Police say tips from the community resulted in his arrest.