(CBS) – This week’s aborted attempt by thieves to steal high-end cars from a Northwest Side dealership shows how auto sellers are fighting back against the crime trend.

And foiling the auto heist was a security company with ties to former Chicago Police Supt. Garry McCarthy.

The would-be thieves cased the dealership before making their move, getting inside by tossing a brick right through a window. But they were being watched the entire time.

The incident occurred early Tuesday at the Marino Chrysler Dodge Jeep dealership in Portage Park.

Surveillance video shows a dark car pull up to the dealership. One suspect gets out and throws a brick through the service door window. The group then drives away.

“They waited probably three minutes before they came back to see if there was a police response from the break,” says McCarthy, now a security consultant.

No audible or silent silent alarm went off, so the burglars come back.

One guy hops through the small cut out window, wiggling his way inside. He opens the door for four other masked and hooded men, who go for the cars.

McCarthy is now a partner with United Security, which was monitoring video of the dealership – live. They called police.

The group at the dealership got frightened and bolted — possibly, McCarthy says, because they were listening to police scanners. The burglars drove away just minutes before police arrived.