A critical police intervention may have prevented further bloodshed in the case of a Minnesota man accused of recently killing two people and injuring two others, authorities say.

Brooklyn Park Police Chief Mark Bruley said on June 17 that a police response to the home of state Representative Melissa Hortman likely disrupted an escalating plan by the alleged gunman, Vance Boelter. The response came after an off-duty sergeant heard that a shooting had occurred at the residence of state Senator John Hoffman and immediately sent two officers to check on Hortman’s home.

When officers arrived, they discovered Boelter’s vehicle in the driveway.

“Had they not foiled the plan, you know, essentially took his vehicle away from him, which involved all his maps, all his names, all his weaponry — I would be very scared what it would look like over the next few hours that had we not done that,” Bruley said during a press conference announcing federal charges against Boelter.

Boelter allegedly fled on foot, prompting a two-day manhunt that ended with his arrest without further incident.

He is accused of fatally shooting Representative Hortman and her husband, Mark Hortman, and injuring Senator Hoffman and his wife, Yvette Hoffman, in separate incidents. Authorities say Boelter arrived at both homes wearing a uniform resembling law enforcement attire and driving a black SUV outfitted with emergency lights and a license plate reading “police.”

Federal prosecutors have charged Boelter with two counts of stalking, two counts of murder and two counts of firearm-related offenses. In addition to the federal charges, he faces second-degree murder charges filed by the Hennepin County Attorney’s Office, which announced that it also intends to pursue first-degree murder charges.