CHICAGO (CBS)–Chicago police have released surveillance photos of two male suspects who allegedly attacked a McDonald’s security guard on April 7 with a glass bottle.

The McDonald’s at State and Chicago, in the upscale Gold Coast neighborhood, has a history of problems. Chicago police have been called to the restaurant more than 30 times during the past month.

During the recent incident, a security guard asked the two men to leave after they were disruptive to customers and employees at the McDonald’s at 10 E. Chicago Ave. around 3:15 p.m. on Saturday.

The men exchanged words with the security guard before the altercation suddenly turned violent, according to police.

The suspects struck the 57-year-old security guard on the head with a glass bottle and punched him in the head and his body, police said.

The Red Line is just steps from the McDonald’s and is often a meeting point and, in some cases, the starting point for problems.

“If you come downtown, you will be met with force, and you will be arrested if you commit crimes,” said Alderman Brian Hopkins.

For years, the McDonald’s was a natural meetup for teens and young adults. But Hopkins and River North Alderman Brendan Reilly say during the past year, large groups of teens often take public transportation downtown and cause problems in the tourist-heavy area.

“You can’t come down to Michigan Avenue and start punching and kicking random people and not expect to get arrested,” Hopkins said.

“There’s a lot already being done,” Reilly said. “The 18th police district has dedicated a lot of extra resources to that intersection.”

Hopkins agreed.

“When you get large groups of kids, if they are behaving, wonderful. But police monitor and keep an eye out, and if a certain group of kids start to act up, they will be asked to leave. And if they are committing crimes, they will be arrested,” Hopkins said.

In addition to the attack on the security guard, 21 people were recently arrested for causing all sorts of issues in popular nearby tourist areas, according to police.

As warmer weather approaches, police have increased their presence in the area to try to quell the violence.