The brother of a man accused in a string of random shootings that terrorized the Phoenix area for more than a year was arrested Thursday in the stabbing of a homeless person.

Jeff Hausner, 40, was arrested for investigation of attempted murder in the April 14 attack, police said.

Police Sgt. Andy Hill said the stabbing was not previously part of the so-called Serial Shooter investigation, but officials have added it to the list.

Hausner's brother, Dale S. Hausner, 33, was arrested in August, along with his roommate, Samuel Dieteman, 31. Both men were charged with murder and attempted murder in 16 random late-night shootings, two of them fatal. They have pleaded not guilty.

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Dieteman was identified as being with Jeff Hausner when the homeless man was attacked, police said.

According to investigators, the victim asked Jeff Hausner for money as the pair left a supermarket. Hausner said, "Yeah, just a minute," then turned his back and spoke with Dieteman for a moment before reaching into a pocket.

When he turned around, Jeff Hausner allegedly stabbed the man in the stomach. In October, the victim identified Jeff Hausner and Dieteman in a photo lineup, police said.

Jeff Hausner told reporters he had nothing to do with the stabbing or the serial shootings as police escorted him to jail.

"Neither did Dale," Jeff Hausner said. "We're both innocent."

Hill said authorities do not plan to charge Dieteman in the stabbing, and Jeff Hausner is not considered a suspect in any of the other Serial Shooter attacks.

Jeff Hausner did not have a prior criminal record, according to prison and court records.

The Serial Shooter case is one of two serial predator cases under investigation by Phoenix police. In September, police arrested a former construction worker named Mark Goudeau in two sexual assaults linked to a string of attacks by the so-called Baseline Killer.

Authorities are investigating a total of 37 random shootings that killed seven people and wounded 17 since May 2005.