CHICAGO (WLS) — For a third night, when 6 p.m. came around, kids under 18 will have to be accompanied by an adult that is 21 or older.All visitors also must pass through security checks before exploring Millennium Park.This is the first weekend of these new measures and despite the new rules , there was more violence Friday night just outside the park.The Chicago Police Marine Unit tweeted photos of a gun recovered in the Chicago River that was allegedly used in the latest incident. A 22-year-old man allegedly exchanged gunfire with an off-duty Cook County Sheriff’s deputy who was working Millennium Park security.Police said that man refused to be wanded at one of the entrances to the park. He ended up hopping a fence, according to police, and was confronted by security before being shot in the buttocks.He was still able to run off but was later arrested along the Riverwalk. That’s when police said he tossed his weapon into the water.That shooting marks the second in less than a week in or around Millennium Park. Last Saturday, a 16-year-old boy was gunned down near the “Bean.” However, the recent violence doesn’t seem to be keeping visitors away.”I’m here maybe once a year, and every time I’m here, it’s such a beautiful atmosphere,” said Ariel Ortiz, a Millennium Park visitor. “Everyone’s really nice. It’s unfortunate that you see something so iconic and you think that type of stuff’s going on.””No, it hasn’t really changed my mind about visiting at night or anything like that, just always staying vigilant anyways,” said fellow Millennium Park visitor Sarah Webb.Officials said visitors should be prepared to show identification. Student and military IDs may be accepted.