By Dana Kozlov

CHICAGO (CBS) — It only took seconds.

Surveillance video shows three people throwing bricks through the windows at an alderman’s office. And it’s not the first time it’s happened.

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CBS 2 Political Investigator Dana Kozlov reports from CPD headquarters and spoke to Chicago Ald. Ray Lopez (15th) about why he’s being attacked.

Ald. Ray Lopez (15th) gets back to some routine business, after a day that’s been anything but routine. Hours earlier, three people smashed the front windows of his 47th Street office. It’s the third time it’s happened in the past four months.

“But what this tells me is that the gangs are struggling to maintain their grip on this neighborhood. That’s what this tells me,” Lopez said.

Lopez said he has no doubt gang members are the vandals in this case. Why now, and again, he isn’t sure. Lopez said it could be retaliation for the arrest of a gang leader this week. Or it could be related to one thing he and his husband Hugo are doing to try and push violent gang members out of his ward.

They keep detailed files of buildings with drug or gang activity. They call them their troubled building files. When the evidence of problems is overwhelming, they send the building owners letters, putting them on notice that things need to change.

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“Then we give them two weeks to give us a call to discuss litigation efforts. And if not, we proceed with the department of buildings and CPD to go at ’em hard,” Hugo said.

That can include taking the  building as the law allows. The latest round of letters went out this week.

“We’ve been actively going after our gang members’ landlords. And doing a very aggressive push to get residents up in arms and fighting back for their neighborhoods,” Lopez said. “I know that plays a part of this.”

In addition to the office, their home has been vandalized too. They accept it as part of their anti-gang, reclaim the ward crusade, with the support of 9th District police. Asked if the incidents give him pause, Lopez said no.

“The answer is 100% no. This is a war. This is a battle we’re in,” he said.

Lopez said the city is supposed to keep track of the troubled buildings but is not doing so effectively at this time. As for the vandals, Lopez believes they have a pretty good idea of who is responsible. But so far, police have not arrested anyone in connection with the crime.

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