Trio accused of making petrol bombs and plotting attacks, but supporters say suspect materials were beer-making kit.

Three protesters arrested in a late-night raid days before the start of this weekend’s 60-nation NATO summit in Chicago have been charged with terrorism for possession of explosive devices, police and their attorney have said.

The men have been accused of making petrol bombs and planning to attack US President Barack Obama’s campaign headquarters, the home of the Chicago mayor, Rahm Emanuel, and other targets during this weekend’s conference, prosecutors said on Saturday.

The three were arrested on Wednesday night in a raid of an apartment in the city’s South Side Bridgeport neighbourhood ahead of the two-day meeting.

The Chicago Police Department (CPD) said the men were charged with conspiracy to commit terrorism, providing material support for terrorism, and possession of an explosive incendiary device.

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

The suspects were each being held on $1.5m bond. They are believed to have come to Chicago late last month to take part in May Day protests. Six others arrested on Wednesday in the raid were released on Friday without being charged.

‘Beer-making’ materials

“The charges are utterly ridiculous. [The] CPD doesn’t know the difference between home beer-making supplies and Molotov cocktails,” said Natalie Wahlberg, a member of the Occupy Chicago movement protesting over income inequality.

Supporters of the three men maintain that the equipment in question was intended for use in home beer-making.

The National Lawyers Guild (NLG), the group of volunteer lawyers representing the protesters, said police “broke down doors with guns drawn and searched residences without a warrant or consent”, according to a statement on the group’s Facebook page.

The police department declined to comment on the details of the raid conducted by a special investigation unit.

President Barack Obama and representatives from some 60 countries are to discuss security in Afghanistan beyond the 2014 international troop withdrawal deadline.

Thousands of protesters are expected to rally nearby on Sunday, prompting a massive deployment of security personnel.

“Sunday will be the day the protesters get closest to the summit, and it will be the day we see the largest number of protesters,” said Jeff Cramer, a federal former prosecutor who now runs the Chicago office of a global security consultancy.

“There are certainly going to be arrests and maybe a scuffle or two. I would be surprised if there weren’t.”

The Afghan government is expecting a promise of $4bn annually for another decade after 2014 to be fulfilled at this weekend’s summit.

The promised funds from the United States and its allied nations in the International Security Assistance Force, will be used to support increases in the number of Afghan soldiers and police, who are expected to take over all security responsibilities in the nation following the December 2014 troop withdrawal.