Ontario's Special Investigations Unit has cleared four York Regional Police officers in the Jan. 28 shooting death of a man in Richmond Hill, ruling that none of the officers fired the fatal shot.

The man was suspected of killing his ex-girlfriend the night before his death, and SIU investigators say he shot himself.

"There is no indication that any of the subject officers discharged their weapons," said acting director Joseph Martino in a news release issued Wednesday about the case of Paul Black.

"In addition, notes subsequently found in Mr. Black's resident indicated he was planning to take his own life. In these circumstances, it is apparent that Mr. Black's death was the result of a self-inflicted gunshot wound for which the subject officers bear no responsibility," he said.

According to the SIU report, Black made two 911 calls to York police requesting assistance, but cut off the call both times.

Police traced the second call to a Richmond Hill park near the intersection of Palmer Avenue and Lennox Avenue.

They approached and saw the 44-year-old Markham resident in a playground area sitting on a piece of equipment.

"As they approached Mr. Black on foot, they noticed he was holding what appeared to be a firearm in his right hand. The officers drew their firearms and ordered Mr. Black to drop his. He refused," it said.

As police closed in and ordered him to drop the firearm, Black told officers his gun was a fake, he said.

However, he pointed the firearm at the ride side of his head and pulled the trigger three times, making adjustments to the firearm twice. On the third try, the firearm went off.

Police administered first aid and paramedics rushed Black to Toronto's Sunnybrook Health Sciences Centre, but Black died at around 8:20 a.m.

Only one of the four officers consented to an interview, although he wouldn't provide his duty notes. Five other police and three civilian witnesses were interviewed during the SIU investigation.

The SIU is an arms-length agency that investigates when police officers are involved in an incident where someone has died, been seriously injured, or alleges sexual assault.

When their fatal encounter with Black was happening, York police didn't know that Toronto police were seeking Black as a person of interest in the shooting death of Andrene Graham.

The 40-year-old woman had been found shot to death near the Dufferin Mall on the evening of Jan. 27.

Toronto police said on Jan. 30 that Graham had been in a three-year relationship with Black that ended in the summer of 2011.