Amid the protests against police brutality spreading across the country, Dallas is still haunted by the death of five officers at the hands of a lone gunman. However, some were concerned by the manner in which the police ended a standoff with 25-year-old Micah X Johnson, the suspect behind the shooting.

The standoff ended early Friday morning when the police detonated a bomb robot, killing the suspect. The Dallas Police Department defended its action saying that the bomb was “a last resort.”

In a statement published Saturday, the Dallas Police Department said, “When all attempts to negotiate with the suspect, Micah Johnson, failed under the exchange of gunfire, the Department utilized the mechanical tactical robot, as a last resort, to deliver an explosion device to save the lives of officers and citizens.”

Police used the Remotec, Model F-5 with claw and arm extension and an explosive device of C4 with a “Det” cord. The contraption weighed about a pound.

Dallas Mayor Mike Rawlings said that this device can be used in similar situations across the country but only as a last resort. He told USA Today, “The key thing is to keep our police out of harm’s way, and this was able to do that and accomplish the tactical objectives we had.”

Rawlings said the decision to use the robot was ultimately made by Dallas Police Chief David Brown. “He is the officer in charge, and I think he made the right call,” Rawlings said. “We spent a lot of time with SWAT forces talking to this individual, trying to bring him out peacefully. It was obvious that he was escalating his bellicose nature and verbosity, if you will.”

The suspect, Micah Johnson, reportedly lived with his mother and was in the U.S. Army Reserve from March 2009 to April 2015. He was honorably separated from the reserve. He served in Afghanistan from November 2013 to July 2014. He even won awards for his service, including the National Defense Service Medal and Army Service Ribbon.