Previously in the area, two Chicago police officers were shot with a high-powered rifle while driving in an undercover van in May 2017, one officer was hit in the arm and hip, the other in the back. Another officer was shot in the leg in July 2017 while chasing down robbers in the vicinity of 46th Street and Ashland Avenue. The Back of the Yards neighborhood had become a hotbed for gang-related shootings in the past two years, leading to the deaths of 50 people out of the more than 140 who had been hit by gunfire from the fall of 2016 to the end of 2017 by gang members wielding rifles as their use spread across the South and Southwest sides. ATF agent Kevin Crump was not hit by rifle fire. Sources said 9 mm bullet casings, presumably from the suspect's handgun, were found by investigators. A Chicago police officer also returned fire but did not manage to hit anyone. The shooting prompted a massive manhunt for the gunman, as hundreds of officers from specialized gang and organized crime units were reassigned to take part in the search for the suspect while a $61,000 reward was also offered in the case. The FBI and ATF each offered a $25,000 reward for information. The U.S. Marshals Service committed $10,000 and community activist Andrew Holmes $1,000. Police and federal agents scoured the Back of the Yards neighborhood for days after the shooting, executing at least eight search warrants. Agents in full armor used battering rams to knock down doors over the weekend.