Investigators have cleared the Ottawa police officers who fatally shot an east-end robbery suspect in early March.

The province's Special Investigations Unit ruled the officers had an "honest and reasonable belief" that Paul Jeffrey was prepared to use lethal force against them - despite the fact the gun he waved turned out to be a replica.

"Even though the pistol was not real, Mr. Jeffrey behaved in a manner that would cause a reasonable person to conclude that it was real," SIU Director Ian Scott said in Friday's release.

Jeffrey, 27, was shot by police at 7 p.m. on March 6 after a reported armed bank robbery at a TD Canada Trust branch on Montreal Road.

Responding officers saw Jeffrey fleeing the area on foot, with what appeared to be a black pistol. At one point he told an officer he might shoot, according to the SIU's report.

Other officers were alerted to the danger via radio. Jeffrey continued to point the gun at police during the foot chase, which prompted four officers to open fire near Rideau High School.

There was no evidence to determine which police officer fired the fatal bullet, according to the SIU, which investigates all police incidents with the public that involve serious injury or death.

Scott said the officers had every reason to believe Jeffrey was prepared to cause harm.

"First, he was running from a recently consummated bank robbery," he said in the statement, "Second, he threatened to shoot an officer. Third, he ran at the officers with the replica gun held in a manner strongly suggesting that he was going to shoot one of them. And finally, the replica could easily be mistaken for a real handgun."