CHICAGO (WLS) -- Please note: This content may be disturbing for some viewers
A group of pro-Palestinian, anti-Democratic National Convention protesters confronted Chicago police Tuesday during what began as a rally outside the Israeli Consulate downtown.
Dozens gathered about 7 p.m. outside the consulate, located at 500 W. Madison St. in the West Loop, over 1 mile from the United Center, where the DNC is taking place this week. Some pro-Israel protesters could be seen as well.
After several speeches, protesters burned at least two flags, one of which was an American flag and another was an American flag with the star of David.
The group then moved into the street and began to walk.
A crowd of about 200 protesters attempted to break through a police bike line and clashed with officers. Fighting broke out, and demonstrators were unable to break through, but still escalated the situation.
Hundreds of Chicago police officers in riot gear, face shields, and with batons surrounded the group in an effort to get the protesters to disperse, at times forcing them onto the sidewalk.
But the demonstrators did not disperse, instead holding a standoff with police. Protesters were also seen hitting police with wooden placards.
CPD Supt. Larry Snelling stared down the crowd from the frontlines.
Protesters again tried to engage with police, but were then funneled through the Loop by a combination of bike police blockades and uniformed bodes. Some protesters left and others marched on near Union Station, where they were again pushed back.
Several arrests were caught on camera. One of the leaders of the protest was seen being arrested as well.
Things ended with the last few dozen protesters at Canal and Monroe at the Katten building. The few left climbing onto signs were forcibly taken down and carried off by Chicago police to waiting city buses.
The protest ending in a whimper rather than a bang. No shots were fired. No pepper spray was deployed, and no Tasers were used.
A group called Behind Enemy Lines organized the rally, which was not permitted by the city.
SEE MORE: Crews add new fencing around United Center after breach during DNC; 13 arrested in protests
The organization said prior to the DNC, they have had multiple protests, distributed pamphlets and organized others to stand with Palestinians and denounce the DNC.
Pro-Palestinian leaders representing Monday's March on the DNC said they were not associated with Tuesday's rally.
Snelling had addressed the protest earlier Tuesday.
"Well, what I can tell you is you never know what to expect from a group like that, but, what I can tell you is what I expect from our side, what I expect from our Chicago police officers, who are going to be responding to that. And, regardless to what they're saying from the CPD aspect of it, we're going to rely on our training. We're going to stay focused, stay focused on First Amendment protection, but we're also going to make sure that we protect everyone in this city," he said.
There was concern because Behind Enemy Lines invoked the violence of the 1968 Democratic National Convention for what could play out Tuesday, vowing to target Chicago police, politicians, delegates and media.
According to a website for the group, there were suggestions of violent tactics. And, just a few months ago, members from the organization crashed a DNC volunteer recruitment event.
According to a Chicago police report obtained by the I-Team, infiltrators "grabbed a microphone" and "pushed" a volunteer when security "attempted to take down" the protesters. But, they all "ran towards the exits, fleeing."
Behind Enemy Lines denied CPD's version of events, telling the I-Team "We did not 'flee' we were forcibly removed by United Center security." The group said protesting the DNC and volunteer recruitment event "was the right thing to do."
The incident was concerning enough that it made a threat assessment by the FBI, Secret Service and CPD, citing the group's intent to cause "further disruption to the DNC."
"We've practiced how we're going to respond, how we're going to move assets around, if necessary. So, we'll assess the situation as it goes along, and we'll be able to move any type of resources or assets that we need to make sure that we keep that situation under wraps. We are prepared," Snelling said.
Behind Enemy Lines is the same extremist group that unfurled a protest inside the Art Institute of Chicago last November; and an American flag was burned at one of their Stop-the-DNC rallies outside City Hall in March.
Retired CPD Lt. John Garrido was on the front lines of civil disturbances and daily police work for decades. Garrido said Tuesday's unapproved protest outside the Israeli Consulate would be of more concern than Monday's fence breach because police had to cover the DNC and another front: downtown.
The protest also affected Metra riders.
Metra said Ogilvie Transportation Center's Madison Street entrance would close at 5 p.m. due to the planned protest. Riders were told to enter through the French Market doors one block north on Clinton Street.
Commuters were told to allow extra time, Metra said. A sign was posted on the train station Tuesday.
In a statement, the Consulate General of Israel to the Midwest said, "We are appalled to see violence during the protest in front of our offices. This is anything but peaceful and completely contradictory to the spirit of the DNC. This vocal minority does not represent the vast bipartisan majority of Americans who stand strong in support of Israel.
"It was incredibly heartwarming to see many Americans countering this hate in front of our office, echoing the strong bond between America and Israel.
"We are beyond disappointed with the ongoing support the mayor has been giving to the anti-Israel protests in Chicago, particularly during the DNC, and his continued disregard for the large pro-Israel and Jewish community in the city.
"Lastly, we are grateful to all the law enforcement officers who are out protecting the city during the DNC. We applaud their self-sacrifice and countless hours of work to ensure the safety of all Chicagoans."
City spokespeople said officials would provide a summary of the protest at a press conference at 11 a.m. Wednesday.
ABC News contributed to this report.