Deputy Commissioner Marianne Ryan said Monday that the shooting came from "out of the blue" and the officers are lucky to be alive.
Police have said shots were fired at the RCMP detachment in St. Paul, a small town east of Edmonton, and within 30 minutes a police vehicle pursuing a suspect inside a truck was rammed on a downtown street.
A shootout followed and the suspect, health food store owner John Quadros, died at the scene.
About the same time, RCMP discovered a Catholic priest, Rev. Gilbert Dasna, had been shot dead inside his rectory. Police have not said whether the two incidents are linked but do not believe the public is at risk. Autopsies on both bodies are to take place Tuesday.
Ryan has talked with all three wounded officers. She said bullets smashed through a cruiser's windshield and grazed one officer's hand, while another officer was hit with shards of flying glass. The two men were treated and released from hospital.
The third officer, a woman with about five years on the force, received the most serious injuries when the RCMP truck she was riding in was struck. The impact crushed her lower limbs, said Ryan.
She visited the officer in hospital after she had surgery that placed pins in both her feet.
"She actually told me that when she was extricated from the vehicle, she felt like her toes were touching her shins."
The officer's bulletproof vest, seatbelt and a deployed airbag likely saved the rest of her body from injury, said Ryan. She still faces more surgery and rehabilitation, but is anxious for the day she can return to work, "which is truly remarkable."
Police were also dealing with the aftermath of another shootout on Sunday which left a suspect dead and an Edmonton police officer with non-life-threatening injuries.
It happened while four Edmonton police officers were trying to execute an arrest warrant on 24-year-old David Charles Sandaker, who had been named by police last month as a suspect in the shooting death of 38-year-old Michael Alan Hill.
Ryan said officers are trained and prepared to handle anything, even surprise attacks, but she wonders whether more can be done to improve their safety.
"Those are the things that keep me awake at night," Ryan told reporters.
"You can never predict where these things are going to happen and when they're going to happen. But we continue to examine our training and our policies and make sure they all do go home at night."
Ryan couldn't say if Quadros was known to police.
Justice officials said the 55-year-old had faced charges going back to July 2010 of assault and mischief under $5,000. They were dealt with through alternative measures.
The RCMP and Alberta's Serious Incident Response Team, known as ASIRT, is helping with the investigation. ASIRT is a provincial unit that reviews the use of force by police.
Clifton Purvis, the head of ASIRT, said investigators will co-operate with the RCMP's review so as to not hinder that work in any way. ASIRT's goal is to determine if an officer caused a death and whether or not it was justified.
As well, Mounties in St. Paul issued a news release asking people who were in a red Cavalier that was near the shootout to contact police as soon as possible.
"The occupants of this vehicle are believed to have information that would be valuable to the investigation," Mounties said.
Meanwhile, the St. Paul diocese announced details of plans to hold vigils and a service for Dasna. Prayer vigils will be held Friday in St. Paul and Saturday on the Saddle Lake First Nation.
Funeral prayers will be held in St. Paul on Sunday and on Monday the funeral will be held, also in St. Paul, though Dasna's remains will be sent for burial to Nigeria.
— With files from CHED, Global Edmonton, CTV Edmonton
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