“Most of our officers have some understanding of Mr. Greene,” Urbandale Police Chief Ross McCarty told reporters at a news conference Wednesday.

Dallas County sheriff’s deputies and Iowa State Patrol officers took Greene into custody around 9:30 a.m. Wednesday, two hours after police officials identified him as the lone suspect in the shooting deaths of Urbandale Officer Justin Martin and Des Moines police Sgt. Anthony Beminio.

According to a criminal complaint, Scott Greene called police on Oct. 16 to report that his mother slapped him in the face around 5:15 p.m. Greene told two Urbandale police officers that he and his mother were fighting earlier in the day over a service dog belonging to Greene’s daughter that he kept in the house, according to the complaint.

Greene told police that his mother slapped him during the scuffle.

Little is known at this point about Greene’s employment history.

YouTube videos from a person identifying himself as Scott Greene show a confrontation between him and Urbandale police officers outside Frerichs Field in Urbandale last month.

Urbandale chief talks about Scott Michael Greene’s history with police.