Published: May 19, 2012 8:43 PM EDT

CHICAGO (AP) - Three men arrested when police raided a Chicago apartment had been planning to attack President Barack Obama's campaign headquarters, Mayor Rahm Emanuel's home and other targets, including police stations and squad cars, prosecutors said Saturday.

The trio was arrested Wednesday in a nighttime raid in the Bridgeport neighborhood on the South Side. They're accused of trying to make Molotov cocktails ahead of the two-day NATO summit that starts Sunday.

The three were charged with providing material support for terrorism, conspiracy to commit terrorism and possession of explosives.

Defense attorneys told a judge that undercover police are the ones who brought the Molotov cocktails, and that their clients had been entrapped. The men were each being held on $1.5 million bond.

They apparently came to Chicago late last month to take part in May Day protests. Six others arrested Wednesday in the raid were released Friday without being charged.

Chicago police Lt. Kenneth Stoppa declined to elaborate on the case beyond confirming the charges against the three who were still in custody.

Police identified the men being held as Brian Church, 20, of Ft. Lauderdale, Fla.; Jared Chase, 24, of Keene, N.H.; and Brent Vincent Betterly, 24. A police spokesman gave Betterly's hometown as Oakland Park, Mass., but no such town exists. There is an Oakland Park, Fla., that is near Fort Lauderdale.

Activist Bill Vassilakis, who said he let the men stay in his apartment, described Betterly as an industrial electrician who had volunteered to help wire service at The Plant, a former meatpacking facility that has been turned into a food incubator with the city's backing.

Vassilakis said he thought the charges were unwarranted.

"All I can say about that is, if you knew Brent, you would find that to be the most ridiculous thing you've ever heard. He was the most stand-up guy that was staying with me. He and the other guys had done nothing but volunteer their time and energy," he said."

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