As Pittsburgh prepares for Beyonce to make a tour stop in the city, some venues across the country have seen protests for and against the singer.

Some groups have protested while wearing “Police Lives Matter” shirts. Others groups have worn “Black Lives Matter” shirts.

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Members of the Nation of Islam have also stood outside at some of the venues.

On Wednesday, some plainclothes Pittsburgh detectives were told to bring their uniforms and riot gear in case they are needed at Heinz Field on Tuesday, WPXI'S Target 11 Investigator Rick Earle reported. Eight detectives were also told they would need to perform "Homeland Security-type patrols" on the North Shore that day.

Pittsburgh police spokeswoman Sonya Toler would not comment on security measures, but told Earle the following: “In doing our due diligence, we've seen a pattern across the country and we are hopeful nothing happens here, but it's our responsibility to be on the ready to protect visitors and residents.”

The NFL’s clear bag policy will be implemented at Tuesday’s concert. Parking lots will open at 3:30 p.m., with gates opening at 5:30 p.m.