The suspect wanted in the deadly shooting was arrested Sunday night in Mt. Airy.
"We knew something had happened. We didn't know what had happened."
A Cumberland County deputy shot a person who lunged at them with a knife, CCSO said.
Four law enforcement officers were shot Saturday morning while responding to a residence in a rural area south of Topeka, Kansas.
Sean Grayson, 31, could be sentenced to up to 20 years in prison, or probation. Sentencing is scheduled for Jan. 29.
Jury deliberations are underway Tuesday in the murder trial of former Sangamon County Sheriff's Deputy Sean Grayson.