Vancouver Mayor Gregor Robertson says the city is pulling out all the stops to track down the anarchist group who claimed responsibility for setting a house on fire early Wednesday morning.

Robertson said he understands the concerns of anti-gentrification activists in the city’s East Side, but any protests involving criminal actions will not be tolerated.

“There could have been innocent people at risk or dying with a fire like that. We cannot take that kind of a risk,” Robertson said. “When there’s criminal activity like that the VPD has a responsibility to deploy all of their tools to bring them to justice.”

The Mayor said there are currently two active neighbourhood planning processes in East Vancouver, and they are the best place for residents to make their voices heard.

“People have a right to protest, they do not have a right to break the law,” he said.

The fire, which police confirm was arson, was set at an under-construction duplex at Victoria Drive and 1st Avenue, destroying the structure and damaging a neighbouring property.

No one was injured in the blaze.

A group known as the Anti-Gentrification Front claimed responsibility for the fire in an email to CTV News that threatened similar attacks were coming.

“Last night we burned down a yuppie development,” it reads. “The class war is heating up. We have no intention on stopping.”

The message reads like a call-to-arms for East Side residents, warning them that rents will rise and they will be pushed out of their homes if nothing is done.

“We are tired of seeing our lives and memories being torn down one development at a time. We wish and will create fear for developers.”

Another unsettling message reading “We’ll be back” was also spray-painted on a portable toilet at the back of the property along with the anarchist symbol.

Police are in the process of canvassing the neighbourhood and working to verify who is responsible for the fire.

They said the email, while alarming, doesn’t prove that the AGF is responsible.

In recent weeks, alleged anti-development activists have tried to chain the doors of Pidgin restaurant, stolen a sandwich board from Save On Meats, and smashed the windows of a Commercial Drive pizzeria three times.

With a report from CTV British Columbia’s Jon Woodward