President Barack Obama and NATO leaders agreed on an exit path for Afghanistan on the last day of their summit in Chicago.

Outside the summit, police arrested at least 100 protesters.

Thousands of people turned out during the multi-day summit and the city of Chicago had more than 13,000 officers on hand to make sure everyone stayed safe.

Charlotte-Mecklenburg police officers were also called in to help control the crowds as they marched through city streets.

Most of the protests were peaceful, but not all. Overall, the NATO summit was an intense experience and an opportunity that CMPD could not pass up as Charlotte prepares to host the Democratic National Convention.

“You let the crowd dictate your activity versus you trying to rev up the crowd,” Chief Rodney Monroe told officers.

Monroe led a team of more than 100 officers on the street of Chicago. He said he wanted his officers to see the protest tactics up close, and learn to control crowds by keeping them moving.

“You always want to give people an out. Most confrontations start when there’s no availability for anyone to back down. You always want to leave that option,” he said.

The CMPD officers were split into two units. They moved through the city on buses, ready to respond.

Capt. Jim Wilson told the officers to not take anything personally that a protester might say or do because everything is being caught on camera.

“If some knucklehead in the crowd is trying to get a reaction out of you, you’ve got to be professional,” he said. “Everyone has a phone and they want to provoke you to make you their rally cry.”

Protesters claim an incident caught on cellphone video shows a police van hitting one of the protesters. Other witnesses said the man jumped in front of the van.

But Coleman Smith said most of the protesters are calm.

He traveled to Chicago from Asheville and said people in Charlotte should not fear the crowds that may show up for the DNC.

“It’s peaceful and it will be the same in Charlotte and it’s unlikely that, unless the authorities get out of hand, that anyone else would,” he said. “I’m not living in La-La Land. There’s always the opportunity for the X-factor.”

That X-factor is exactly what CMPD’s officers are preparing for.

Monroe said that the people who want to protest during the DNC should talk to CMPD about those plans and seek a permit.

During the DNC, Chicago police officers will come to Charlotte to assist with crowd control, he said.