As NATO protesters marched by the hundreds to Chicago Mayor Rahm Emanuel’s house, three others were in court Saturday facing terrorism charges for allegedly planning to bomb the mayor’s residence, police stations and Obama’s campaign headquarters during the upcoming summit.

While the delegates from the treaty organization began to arrive and security tightened around the city for Sunday’s kickoff, three men who had been arrested in a raid Wednesday appeared before a Cook County judge, charged with conspiracy to commit terrorism, possession of an explosive device and providing material support for terrorism.

The men — Occupy activists Brian Church, 20, of Fort Lauderdale; Jared Chase, 24, of Keene, N.H.; and Brent Vincent Betterly, 24, of Oakland Park, Fla. — are being held on $1.5 million bond.

Prosecutors alleged they had made Molotov cocktails and had discussed using other weapons, including swords and knives.

Police Superintendent Garry McCarthy said police were responding to an “imminent threat.”

Lawyers for the suspects disputed those claims.

“There are a lot of sensational allegations being made,” said Kris Hermes, a spokesman for the National Lawyers Guild. “This is obviously an effort to chill dissent ahead of the NATO demonstrations.”

As darkness fell, the crowds of protesters who gathered to show support to the terror suspects swelled to nearly 1,000, and there were several tense scuffles with police. At least 10 more protesters were detained, Hermes said.

Police said they made 13 other protest arrests during the week as signs of heightened security grew with wide-ranging parking restrictions and rolling road closures to accommodate motorcades of dignitaries.

The suspects were arrested in a late-night raid on a house in the Bridgeport neighborhood, along with eight others who were detained but not charged. A late afternoon march in solidarity with the suspects, already dubbed “The NATO Three,” soon organized on Twitter.

Meanwhile, the several hundred Occupiers who had descended from across the country for the week to agitate against the military-industrial complex turned their attention Saturday to a personal foe: Rahm.

Angry at the mayor’s decision to close six mental health clinics — part of a reorganization of services the city says is a cost-saving measure — Occupiers donned nurses’ smocks and marched through the streets of Emanuel’s leafy Ravenswood neighborhood, chanting “Health care, not warfare.” They climbed trees in front of his house in full view of a line of bicycle cops and called “Mayor One Percent, come on out!”

The mayor was not at home nor would he be.

“He supports everybody’s right to demonstrate and express their views,” said his spokeswoman, Caroline Weisser.

Since Emanuel was elected mayor of his hometown last year, he has not shied away from the foul language and bare-knuckled tactics honed during his service to two presidents and seven years in Congress. This weekend, he’s serving as Chicago’s chief booster as the city takes the world stage, flooding the streets with police in an effort to avoid any nasty flare-ups during large-scale protests planned for Sunday and Monday.

Emanuel’s relationship with the Occupiers has been contentious since the first protests began in September. Chicago was one of the few in the nation without an encampment; when they tried to set up shop on two separate occasions in October more than 300 were arrested. In January, Emanuel asked for and got stricter rules on parade assemblies that Occupiers dubbed the “sit down and shut up” laws.

“He hasn’t done anything good for the city,” grumbled Jim Gant, 65, a retiree from the city’s South Side. He held a sign outside Emanuel’s home that said “Blame Rahm NATO Chaos.” “He’s a rough character. What brought his reputation in Washington is starting to surface here.”