A man is detained after a standoff between protesters and police on Aug. 18, 2014 in Ferguson, Mo.
Charlie Riedel—AP
August 19, 2014 12:57 AM EDT

Updated 8:24 a.m. ET

The deployment of the National Guard and the lifting of a curfew failed to prevent another night of violent clashes between protesters and police in Ferguson, Mo., late Monday night, as a day of almost eerie calm soon gave way to a night of mayhem and chaos. Protesters overpowered more peaceful demonstrators at about midnight and threw bottles at police, who responded with tear gas, as multiple gunshots were heard ringing out in this St. Louis suburb. Authorities later said 31 people were arrested.

Missouri Gov. Jay Nixon had hoped the National Guard, along with President Barack Obama’s repeated pleas for calm, might finally defuse the situation in Ferguson, which has been rocked by racial tensions ever since the killing of an unarmed black teenager by a white police officer on Aug. 9.

“Let’s seek to heal, rather than to wound each other,” Obama said in his latest remarks on the crisis Monday.

And for much of the day, it appeared as though tensions were cooling. Police had cordoned off parts of the downtown area and were allowing people to peacefully protest, and demonstrators marched up and down the streets with an air of positivity. But the peaceful demonstrators, who have lamented their violent counterparts keeping the town in the national spotlight, were met by a younger, rowdier group at about midnight. A human chain of peaceful demonstrators—including pastors and community leaders—briefly kept the more raucous protesters at bay, with the help of a line of police in tactical gear.

But as the protesters threw glass bottles at police, the police responded with tear gas. And the night once again devolved into the dispiriting spectacle of protesters throwing bottles, police pointing their guns or firing tear gas — in some cases from the open windows of unmarked white minivans, protesters scrambling away, and authorities rounding up people for arrest.

State Highway Patrol Captain Ron Johnson later said his officers had come under heavy attack, including gunfire, but said “not a single bullet was fired by officers,” Reuters reports.

It remained unclear if National Guard troops were at the scene of the latest violence; some reports indicated they were, but the authorities on site appeared to be the state troopers Nixon previously brought into to take control of the situation, along with other local officers. Authorities on the scene said the National Guard was providing operational backup at a police command center nearby, and officials had previously made clear the Guard’s mission would be limited in scope.

“I’ll be watching over the next several days to assess whether it’s helping rather than hindering progress in Ferguson,” Obama said Monday of the National Guard presence.

Shortly before midnight, much of the main downtown thoroughfare where clashes were taking place was sealed off.

With reporting by Robert Klemko/Ferguson, Mo.

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