As the NATO summit approached, Chicago police Friday continued to hold several people suspected of making Molotov cocktails but would say nothing about the arrests, adding to a growing mystery over the nature of the investigation.



Police earlier Friday released from custody — without charging — four of the nine people who were swept up in a late-night Wednesday raid of a Bridgeport apartment building. Two more were released Friday night without charges.



According to law enforcement sources and police reports obtained by the Tribune, the arrests were the result of a monthlong investigation into a group suspected of making Molotov cocktails — crude bombs usually created by filling glass bottles with gasoline.



But the National Lawyers Guild criticized the police raid, saying the nine NATO protesters only had beer-making equipment in their possession.



The nine range in age from their 20s to a 66-year-old grandfather with a heart condition. Several are affiliated with the Occupy movement and had arrived in Chicago in recent weeks from California, North Carolina, Massachusetts and elsewhere.



Details of the investigation remain murky.



Chicago police and Cook County prosecutors so far have declined to publicly discuss or even acknowledge the arrests in the 1000 block of West 32nd Street, even as the conduct of the officers has come under criticism from those arrested and other building residents.



Witnesses described police officers dressed all in black armed with battering rams and guns drawn swarming into the building, conducting warrantless searches and refusing to tell them what was going on.



One resident told the Tribune police taunted him and his roommate, repeatedly calling them communists and using anti-gay slurs.



Adding to the mystery, two other individuals were detained in separate arrests Thursday.



A 24-year-old man was arrested at his Northwest Side home for allegedly conspiring to build Molotov cocktails, while a 28-year-old West Side man, who is on probation for a 2011 conviction for the aggravated battery of a police officer, was arrested for allegedly attempting to possess an explosive device, according to sources and police records.



The second individual was scheduled to appear in bond court Friday but was pulled at the last second for an unexplained reason.



Darrin Annussek, 36, one of the four released Friday, said he was detained for 30 hours, including being handcuffed and shackled for 18 hours in an "interrogation room." He said police refused his request to use a restroom and did not read him his constitutional rights.



"None of us were told why this was happening," other than that he was being held on a "conspiracy" charge, Annussek told reporters Friday outside the Harrison District station.



Annussek, a laid-off social worker, said he began marching in November from Philadelphia to Atlanta "to try and spread the positive message of Occupy Wall Street." He arrived in Chicago in time for the May Day march.



"To be charged with felony conspiracy to endanger anybody's life is not only a slap in the face, it's against everything I stand for," he said.



The wife of the 66-year-old suspect, who was also released Friday without charges, said her husband told her he was trying to get police to return his cellphone, a computer and his heart medicine. She laughed when told about the bomb-making allegations.



"He's a pretty middle-of-the-road, very pacifist kind of guy," she said. "That is the most ridiculous thing."



A 25-year-old resident of the Bridgeport building said he heard a loud bang at about 11:30 p.m. Wednesday as police swarmed into his second-floor unit with guns drawn.



Police pulled his sleeping roommate out of bed, he said.



"The only thing we were told was that we were in the middle of an investigation," said the man, who spoke to the Tribune on the condition he not be identified.



Police found books in the apartment that included one with selected writings by Karl Marx. The resident said police handcuffed him and his roommate, ignored their complaints the cuffs were too tight, repeatedly called them communists and used anti-gay slurs.



"These guys were bullying us, harassing us and mocking us," the man said. "They were cruel."



He said neither he nor his roommate is involved in any NATO protests and did not know any of the nine who were detained.



Another resident, a 26-year-old man, said he was on the back porch outside his third-floor apartment smoking a cigarette when police appeared with guns drawn and began climbing the back fire-escape steps.



The man, who also spoke to the Tribune on condition his name wasn't published, said the officers never physically mishandled him.



"They were very nice about stomping on my civil rights," he said.



Sarah Gelsomino, an attorney with the National Lawyers Guild, confirmed that two people arrested in Bridgeport were released, Daniel Murphy and Robert LaMorte.



They believe that three people who were arrested are still in custody, Gelsomino said. Police would not confirm that.