BRUSHES WITH THE LAW

Investigators search a field near Redfield, Iowa, where the suspected gunman of two police officers who were shot and killed in separate attacks described as "ambush-style" in Urbandale and Des Moines, Iowa, U.S., turned him self in, November 2, 2016. [Photo/Agencies]

Police said it was unclear what provoked the attacks, but he had various brushes with the law. In 2014, he pleaded guilty to interference with official acts in an incident involving police. The same year, he also pleaded guilty to harassment and was ordered jailed. He was charged in 2001 with assault causing bodily injury and criminal mischief, but those charges were dismissed.

Parizek said Greene was under guard at a hospital. Asked about the suspect's condition, he said, "Sick. I don't know." Parizek said charges against Greene could come after police interview him and gather forensic evidence from the scene. An arraignment could happen as early as Thursday morning, he said.

"Most of the officers that have been in the city have some understanding of Mr. Greene," McCarty said. "They've taken trips to his house, or delivered service to him. Never to anything of this extent though."

In a 2007 bankruptcy filing, Greene said he was single with three children.

In Washington, U.S. Attorney General Loretta Lynch urged Americans to avoid jumping to conclusions about the shooter's motive.

"This is a time of particular tension and mistrust between law enforcement and many communities," Lynch said at an event for veterans at the Justice Department. "There is no message in murder. Violence creates nothing. It only destroys."

Democratic U.S. presidential candidate Hillary Clinton said on Twitter she was "Heartbroken for the families of two brave officers who were killed in Iowa. There's no justification for this kind of violence."

Republican candidate Donald Trump said on Twitter, "An attack on those who keep us safe is an attack on us all."

(Reporting by Brendan O'Brien in Milwaukee, Julia Harte in Washington, Gina Cherelus, Dave Ingram and Michael Flaherty in New York and Rory Carroll in San Francisco; Writing by Scott Malone; Editing by Will Dunham)