The RCMP has released some key details that they've garnered from their ongoing investigation into the devastating mass murder — the deadliest in Canadian history — that took place in Nova Scotia last weekend.

Citizens of the coastal hamlet of Portapique, as well as across the country, are still trying to wrap their minds around the shocking rampage that took the lives of 22 people and injured another three over the course of late April 18 and early April 19.

Nova Scotia RCMP Superintendent Darren Campbell provided the first somewhat comprehensive timeline of the crimes to the public in a press conference on Friday, saying that, first and foremost, "to call this a tragedy would be an understatement."

The events unfolded over the course of more than 12 hours (though it was rapidly evolving) in three "clusters" that include 16 separate crime scenes.

Campbell says there were 3 clusters of incidents. A total of 22 victims were killed. He says some people who died lost their lives trying to save others. They are heroes #Portapique #NovaScotia

— Natasha Pace (@NatashaPace) April 24, 2020

The first spate of shootings, which occurred on the night of April 18 in the area of Portapique — a place Campbell described as a "quiet and peaceful" community with only 100 year-round residents — started with an attack on the suspect's girlfriend, who thankfully managed to escape and hide in the nearby woods.

(When she emerged hours later, she was the one to provide police with integral details about the killer, 51-year-old Gabriel Wortman.)

The first 911 call in relation to the spree was about a shooting near a Portapique residence, where police arrived at around 10:26 p.m. A male victim was found departing the area with gunshot wounds he said were sustained from being shot at by a passing vehicle while he was driving.

He noted that the suspect was heading toward Portapique on the only road into and out of the community, Portapique Beach Road, and that the shooter's vehicle looked like a police car.

When officers arrived on the scene in the heavily wooded rural town, they discovered "several people" deceased on the roadway and multiple buildings engulfed in flames. They proceeded to secure the area, checking nearby homes for both the suspect and potential victims, coming across additional bodies at more than seven locations as they did so.

A total of 13 were shot and killed in Portapique.

A critical response team and specialized services including police dogs, helicopters and crisis negotiators were called in as investigators learned that the possible suspect was identified as a man who lived in the area, and whose home and property had also been lit on fire — including two mock police cars, as he was "known to own several vehicles that looked like police vehicles."

The search continued overnight, and it wasn't until Wortman's girlfriend emerged from hiding around 6:30 a.m. on Sunday morning and called 911 — giving details about Wortman's car, apparel and firearms — that the RCMP was able to issue a directive for people to be on the lookout for a man and vehicle matching Wortman's description.

pic.twitter.com/FxHWixcBsd

— The Blue Djin ➡️ Not Dead Yet 📚🔭⚾️☕️🇮🇸 (@TheBlueDjin) April 24, 2020

It was on the morning of April 19 that officials started receiving 911 calls about the second cluster of shootings, which took place 16 km away near the community of Glenholme. Wortman showed up at a private residence there and killed two men and one woman before setting the house on fire. At least two of these victims were known to the suspect.

He also attempted to gain access to another home in the area, but the residents called police and didn't answer the door, which ultimately led to their survival.

As Wortman proceeded north to the Wentworth area, he killed another resident who was out for a walk, and two more people who were driving their cars, at least one of whom he pulled over under the guise of being a member of the RCMP.

More on the list: there was a 911 call in Glenholme area where gunman killed two people and set fire to a home. Those two people knew the gunman, police don't know why he would have gone there to see them. Likely they were people he might have had an issue with, RCMP say.

— Sarah Ritchie (@SarahRitchieTV) April 24, 2020

The third group of shootings was the one that included the death of Constable Heidi Stevenson, who, along with fellow RCMP officer Chad Morrison, was on duty stationed in nearby Enfield on the morning of the 19th.

The two officers were communicating to one another via their radios and were due to meet up at an intersection. Morrison was waiting for Stevenson and spotted what appeared to be her vehicle, but which actually turned out to be Wortman in what looked like an RCMP car.

The suspect drove up to Morrison and opened fire, after which the officer was forced to retreat to seek medical attention for several gunshot wounds.

Stevenson, who was nearby, collided head-on with Wortman as he too fled the area. It was after that point that he took her life, along with her gun and magazines, and set both cars alight.

A passerby who stopped at the scene was also shot and killed, and Wortman stole his vehicle, a silver SUV. He drove southbound to the home of a woman he knew, shot and killed her, and transferred to her vehicle, a red Mazda 3. He also removed his imitation police uniform at this time.

It was after this last murder that Wortman was finally apprehended 22 km away while he was getting gas at the pumps at Irving Big Stop, which tactical vehicles happened to stop at to likewise refuel.

"There was an encounter and the gunman was shot and killed by police," Campbell said, ending the reign of terror at 11:26 a.m. on April 19.

RCMP: Gunman carried on to residence of woman he knew. He shot her, and then transferred into Mazda 3 vehicle. He then drove to gas station in Enfield, where RCMP engaged and he was shot. Concludes around 11:26 am AT (Sun. April 19 - appx 13 hours from first gun call)

— Aarti Pole (@aartipole) April 24, 2020

Police are still considering how much of the attack was pre-meditated, with Campbell saying that the incident with Wortman's girlfriend — which he called a "serious assault" — and her escape could have served as a "catalyst" for the remaining crimes.

As police continue to piece together evidence to trace the shooter's steps in detail, they are asking anyone with additional information to come forward to aid in what is a "very fluid and complicated" investigation.

There are still some gaps in the story, Campbell said, and officials want to "ensure that there was no involvement or knowledge of any other person," and also to understand exactly what happened during this sickening and indelible national tragedy.