INDIANAPOLIS A traffic stop led to the arrest of a 21-year-old after he allegedly violated the terms of his home detention and had a firearm illegally.Indiana Crimes Guns Task Force detectives were conducting surveillance on 21-year-old Demarco Williams, who had a level five felony warrant for possession of a machine gun, on Sunday, Nov. 6.A warrant was recently issued for Williams after he violated the terms of his home detention by removing his ankle monitor, which triggered the warrant, IMPD said.Investigators say Williams had posted photos of firearms on social media. In the images, he was seen holding a black extended magazine, which had black and green rubber bands wrapped around its base.As a convicted felon, Williams is prohibited from possessing firearms under Indiana law.A white Chrysler 300 pulled into a driveway near the 2600 block of Sherman Drive, and Williams was seen getting out of the passenger seat. Detectives, along with IMPD officers, initiated a traffic stop.During the stop, police say Williams failed to comply with officers' verbal commands and made a movement toward the front of his waistband, leading officers to believe he might be reaching for a firearm.IMPD says Williams also tossed an item into the vehicle before being taken into custody without further incident.The driver of the vehicle was also detained. Due to the dark window tint, officers say they could not safely determine if there were other passengers inside the car without opening the doors.When officers opened the rear drivers side door, a black Glock 17 9mm handgun fell out. IMPD said it had an extended magazine with black and green rubber bands wrapped around it, similar to the one seen in Williams photos.Williams was arrested for his warrant and outright arrested for unlawful possession of a handgun by a prohibited person.The Marion County Prosecutor's Office will make the final charging decisions.The Indiana Crimes Gun Task Force has seized 229 firearms and made 199 arrests so far in 2024.