DUBLIN (AP) — Police say two gunmen have ambushed and killed a former top figure in the Real IRA splinter group in the southwest Irish city of Cork.

Witnesses say the attackers approached Aidan O'Driscoll from behind in the street, shot him once in the back, then twice more as the 37-year-old lay on the pavement.

O'Driscoll, the Real IRA's reputed former chief of staff, was pronounced dead two hours later at Cork's hospital.

Police made no arrests following Wednesday's attack. No group claimed responsibility.

The Real IRA issued a statement asserting that O'Driscoll had been expelled for pilfering funds from the outlawed group's criminal racketeering. He had been shot in both legs in 2013 in an apparent effort by Real IRA colleagues to harm, not kill, one of their own.