Two Des Moines area police officers were shot to death while sitting in their patrol cars early Wednesday in what authorities described as separate ambush-style attacks, and police said they captured the man suspected of killing the officers.

Officers responded to a report of shots fired at 1:06 a.m. and found an Urbandale Police Department officer shot. Authorities from several agencies saturated the area after that shooting, and about 20 minutes later discovered that a Des Moines officer who had responded to the initial killing had been shot in a patrol car at an intersection, Des Moines Sgt. Paul Parizek said.

The shootings happened less than 2 miles apart and both took place along main streets that cut through residential areas.

“There’s somebody out there shooting police officers. We hope to find him before somebody else gets hurt,” said Parizek, who stopped briefly during a news conference as he worked to control his emotions.

The shootings follow a series of police killings, including ambushes of officers in Dallas and Baton Rouge, Louisiana. On July 7, five Dallas police officers were murdered. Three were killed later that month in Baton Rouge.

Des Moines and Urbandale Police later said they have identified 46-year-old Scott Michael Greene as a suspect in the killings.

Parizek said investigators determined Greene was a suspect through “a series of leads and investigative tips.”

Police described Greene, of Urbandale, as white, 5′ 11″ and 180 lbs with brown hair and green eyes, last known to be driving a blue 2011 Ford F-150 with Iowa license plate 780 YFR.

“There is a clear and present danger to police officers,” Parizek said. He said officers are now conducting patrols in pairs for protection.

Urbandale Sgt. Chad Underwood said he believes this is the first time an officer in his department has been shot in the line of duty.

Wednesday marked the first time a Des Moines police officer has been shot and killed on duty since 1977, when two died in separate incidents months apart, according to the Iowa Department of Public Safety. With Wednesday’s deaths, 113 Iowa officers have died in the line of duty in 2016, according to preliminary data from the National Law Enforcement Officers Memorial Fund.

Court records show Greene was jailed and charged with interference with official acts after resisting Urbandale police officers trying to pat him for a weapon on April 10, 2014. An Urbandale officer described him as hostile and combative. He entered a guilty plea and was fined.

Two days later Urbandale police were called to answer a complaint of harassment at the apartment complex where Greene lived. The complaint said he threatened to kill another man during a confrontation in the parking lot. He was charged with harassment.

He pleaded guilty and received a suspended jail sentence and a year of probation. Court records show he completed a substance abuse and psychological evaluation.