By Aaron Klein

In a sign of what may be coming, residents of a Chicago condo building located near the site of next month's NATO summit have been asked to leave for the event or risk being caught in a storm of rioters.

WND first reported in August 2011 that radicals, some with ties to President Obama, were planning to riot during the NATO summit.

FOX Chicago News reported the people living in the 17-floor Library Tower building at 520 South State Street were warned in a letter from condo management that "we are STRONGLY recommending that all residents find places to stay during the conference from May 18 through May 21."

The letter specifically warned of riots:

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"In the event of a riot or the potential of one near the building, all access doors will be locked including the garage door," the letter continues. "For everyone's safety, we will be instructing anyone in the building to stay in his or her unit."

While NATO summits often attract crowds of thousands of protesters, the national Occupy movement may add even more chaos to the expected mass protests.

Chicago will be the first American city other than Washington to host a NATO gathering.

Such meetings have previously drawn mass protests that turned violent.

The 1999 WTO event in Seattle devolved into widespread rioting in which more than 40,000 protesters, some using violent tactics, descended on the city, prompting police to use tear gas and rubber bullets. The clash became known as "The Battle of Seattle."

Preparing for outbreaks, the Chicago Sun-Times In July 2011 quoted Superintendent of Police Garry McCarthy as saying he was prepping 13,000 officers under his command for mass arrests of protesters.

"We have to train for mass arrests," McCarthy said. "We have to train 13,000 police officers in arrest procedures and containment procedures. At the same time, we will not stop patrolling the city."

In response, radical groups held a press conference that month in downtown Chicago demanding permits to march during the world summit in May.

Joe Iosbaker of the United National Antiwar Committee, one of the groups planning protests, warned, "The wars and economic policies of the NATO and G8 nations are not just and will be met by protest."

Iosbaker is a University of Illinois-Chicago office worker and a union steward for his SEIU local. His home was raided by the FBI last September reportedly as part of a terror probe investigating material support for jihadist groups.

Obama has ties to many of the activists groups being investigated in that FBI probe.

WND reported Iosbaker and his wife, Stephanie Weiner, worked as leaders of the Chicago New Party, a controversial 1990s political party that sought to elect members to public office with the aim of moving the Democratic Party far leftward. The ultimate goal was to form a new political party with a socialist agenda.

WND previously reported on evidence from the New Party's own newsletters showing Obama was a member of the New Party.

Another group at that press conference planning to protest at the May summits is Code Pink.

Code Pink's co-founder, Jodie Evans, was a fundraiser and financial bundler for Obama's presidential campaign.

Also planning protests is Tom Burke of the so-called Committee to Stop FBI Repression, which has been leading activism against the FBI's reported ongoing terror probes of Chicago and Minnesota anti-war groups.

Burke, a former school custodian who is now a stay-at-home father, belongs to the Freedom Road Socialist Organization, a group mentioned in subpoenas and search warrants issued in the same FBI terror probe.

WND reported on Obama's other ties to the activist groups at the heart of the FBI terror probe, including Hatem Abudayyeh, the executive director of the Arab American Action Network, or AAAN.

WND was first to report that Obama, while serving as a paid director of the far-left nonprofit Chicago Woods Fund, provided two grants to the AAAN.

Obama served at the Woods Fund alongside Weather Underground terrorist-group founder Bill Ayers.

AAAN was founded by a longtime Obama associate, Columbia University Professor Rashid Khalidi. Khalidi's wife, Mona, is president of the Arab American Action Network.