The reward has quadrupled in size for information leading to the arrest and conviction of the man who police said was involved in a deadly triple shooting late last month.

Police are asking for the public's help in finding 38-year-old Terrance Lamb.

[RELATED: Police identify suspect in south Phoenix triple shooting]

Along with up to $1,000 from Silent Witness for an arrest, the U.S. Marshals is offering up $3,000 for a conviction, bringing the total possible reward to up to $4,000, police said.

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Officers said Lamb left the shooting scene near 16th Street and Southern Avenue on June 25 around 4:45 p.m. in a white 1997 Chevy Express van with the Arizona license plate CJK-2031.

[ORIGINAL STORY: Police: 2 dead, 1 hurt after shooting at south Phoenix home]

Two of the victims of the shooting 28-year-old Ja'Cory Ranger and 35-year-old Ricky Elam, Jr., died at the home.

A third victim, who hasn't been identified, was found at the hospital but he survived his injuries.

[READ MORE: Police identify 2 victims killed in triple shooting in south Phoenix]

Police have not said what led up to the shootings or a possible motive.

Anyone with information is asked to call Silent Witness at either 480-WITNESS (948-6377) or 1-800-343-TIPS (8477). Spanish speakers may call 480-TESTIGO (837-8446). (Click or tap phone number to call from this story on your mobile device.) Callers can remain anonymous and could earn a reward of up to $1,000.

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