Manchester explosion: authorities have good reason to call this a terrorist attack, expert says

UPDATE: ISIS claims responsibility for suicide bombing at Ariana Grande concert

A Canadian expert on terrorism and radicalization says there’s good reason British investigators are treating a deadly explosion in Manchester as a terror attack and that their experience with terrorism means they will likely be able to gather information quite quickly.

“They’ve been very, very good in terms of preventing and disrupting many of these plots, this goes back to prior to even before this Islamist-inspired stuff in terms of their dealing with the provisional Irish Republican Army,” Michael Zekulin, adjunct assistant professor of political science at the University of Calgary, said Monday night.

“Just the very fact they’ve been dealing with a threat like this for a very long time, they’ve become quite adept and quite good at piecing these things together.”

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Hours after it happened, U.K. officials had not confirmed that the Monday incident, which police are calling a suicide attack, that killed 22 people and wounded dozens more at an Ariana Grande concert at Manchester Arena was a terror attack.

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But authorities nevertheless treated it as one until they learned otherwise.

READ MORE: Manchester Arena explosion: 22 dead, 59 injured after incident at Ariana Grande concert

“It seems to have many of the hallmarks (of a terror attack),” Zekulin said.

“Is it possible that there’s some other explanation for this type of explosion? You’d think that they’d be able to determine that fairly quickly – you know, something like a gas leak or something along those lines but it seems to be premeditated.”

“It’s what we’d consider to be a soft target… people are going to enjoy themselves, feeling good, letting down their guard… so it sort of compounds the end result of the anxiety or the terror.”

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READ MORE: Manchester Arena explosion: people react with horror to incident that left 22 dead

Britain is on its second-highest alert level of “severe,” meaning an attack by militants is considered highly likely.

In March, four people were killed and 40 injured in a terrorist attack outside the U.K. Parliament. Zekulin suggested Monday’s blast seems to be in keeping with the type of attacks Euorpe has experienced in the past year and a half to two years and that the response will be similar.

“You also have to look at this in the context of being concerned that should there be something bigger going on here, if it was a group or something along that nature, you want to be sure that there’s nothing else that’s imminent in the next hours or days.”

Zekulin said while Britain has a long history of dealing with terrorism, the relationship between security and rights and freedoms continues to evolve as the number of attacks mounts and amid a growing wave of “ultra-nationalism and xenophobia” across Europe.

READ MORE: Timeline of terror attacks in Britain

On Monday night, Rita Katz, terror analyst and the director of SITE Intelligence Group, tweeted that pro-ISIS social media accounts have increasingly called for attacks on the UK and said users of a pro-ISIS forum had called the Manchester blast “a successful and surprising blow” to Britain.

Another high-profile terrorism analyst, Michael S. Smith II, was also tracking pro-ISIS forums in the wake of the blast. He tweeted that a number of pro-ISIS supporters said the deadly incident was justified by airstrikes that killing have killed young Syrians and Iraqis.

“Generally, if ISIS does do something, they claim responsibility for it very quickly,” Zekulin said, pointing out if the blast is confirmed as a terror attack, there are other groups that could claim responsibility.

“The best bet at this point would seem to be ISIS or ISIS-inspired but we don’t know until we actually know.”