Iowa cop killer Scott Michael Greene has been revealed as a proud Donald Trump supporter, and even has a sign in his yard

The man who shot dead two Iowa police officers has a sign promoting Donald Trump in the front yard of the home he shares with his mother.

Scott Michael Greene, 46, was arrested on Wednesday after ambushing Urbandale police officer Justin Martin, 24, and Des Moines police Sgt. Anthony 'Tony' Beminio, 39.

Greene surrendered to a state Department of Natural Resources officer in Dallas County about 9am.

An Iowa man has since been charged with two counts of first-degree murder in relation to the deaths of two police officers.

It has now been revealed the cop killer has a pro-Trump sign in this yard, the Daily Beast reports.

The website quotes a neighbor who said: 'They got a Trump sign, but what’s that got to do with anything?'

It also added the sign could have been placed by Greene's mother, 66-year-old Patricia Greene. Neighbors say the sign was put up in the yard about two weeks prior to the shooting.

A Facebook account belonging to Patricia Greene has a number of pro-military and Blue Lives Matter posts. She does not mentioned Donald Trump by name in her comments.

One post, which was shared last month, reads: 'KILLING A POLICE OFFICER SHOULD BE A MANDATORY DEATH SENTENCE.'

Having the sign in his front yard does not in any way link the shooting to the Republican presidential nominee.

The Trump camp told the Daily Beast Patricia Greene had submitted a request for a sign.

Neighbor tells me that shooting suspect Scott Michael Greene put this Trump sign in his yard approx 2 weeks ago. pic.twitter.com/8HjtthB51I — Grant Rodgers (@GrantMRodgers) November 2, 2016

Greene, pictured waving a Confederate flag in front of African American fans at a football game, shot and killed two officers in separate ambushes on Wednesday

Urbandale police officer Justin Martin, 24 (right), and Des Moines police Sgt Anthony Beminio, 39 (left), have been identified as the officers killed in the shootings

Trump was quick to offer his condolescenes after news of the shooting spread, tweeting: 'Praying for the families of the two Iowa police who were ambushed this morning. An attack on those who keep us safe is an attack on us all.'

Hillary Clinton also commented on the killings, tweeting: 'Heartbroken for the families of two brave officers who were killed in Iowa. There’s no justification for this kind of violence. -H.'

It comes after police said they believe a gun they found by a search dog in a wooden area is the weapon Greene used.

The first officer was shot dead in his squad car at 1:06am outside Urbandale High School. The first crime scene pictured above

The second shot officer was found inside this parked cop car at the intersection of Merle Hay Road and Sheridan Drive around 1:26am (pictured above)

Bullet holes are seen on the side of the first cop's car targeted in the attack

The weapon was found "where no person probably could have found it," Des Moines police spokesman Sgt. Paul Parizek said during a news conference. He said the weapon was found Wednesday, the same day the officers were shot, but he declined to provide details.

The shootings came less than three weeks after the suspect, Scott Greene, argued with officers who removed him from a high school football game where he had unfurled a Confederate flag near black spectators.

Parizek got emotional during Thursday's news conference, thanking the community for its outpouring of support and saying the officers represent "the security blanket you guys sleep under every night."

Both shootings happened in the Des Moines suburb of Urbandale, where the local police department has just 50 officers

Greene was hospitalized following his arrest but was expected to be released Thursday, Parizek said. He said investigations have yet to speak with Greene and a motive remains unclear, but that investigators are looking at possible first-degree murder charges. No formal charges have been filed.

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

In the first shooting, investigators believe the gunman walked up to the officer's car and fired more than two dozen rounds.

'I wouldn't call it a confrontation,' Urbandale Police Chief Ross McCarty said. 'I don't think he may have even been aware that there was a gunman next to him.'

The shootings follow a spate of police killings in recent months, including ambushes of officers in Dallas and Baton Rouge, Louisiana. Five officers were killed July 7 in Dallas. Three more were killed later that month in Baton Rouge.

Beminio had been promoted to sergeant last year after about 10 years on the police force

Martin (pictured second right) graduated from Simpson College in 2015 - the same year he joined the Urbandale Police force

Race was an issue in those cases and others involving unarmed black men killed by officers. Greene is white, as were the officers.

Greene appeared to have issues with people of other races.

In the confrontation at the Urbandale High School football game, which Greene videotaped and posted on social media, he appeared to be trying to antagonize African-American fans when he shook a Confederate flag in front of them during the national anthem, McCarty said.

In the video, officers can be seen asking Greene to leave school property while he insists he was assaulted and his flag was stolen. He demands officers file theft and assault charges, saying someone hit his head and grabbed the flag.

In a back-and-forth with officers that lasts for nearly 11 minutes, officers say they could take a report but they cannot let Greene back inside the stadium because the school has banned him from the property.

They also note they were returning his flag and ask if he purposely wanted to create a conflict by displaying it near African-Americans.

'I was peacefully protesting,' he responds. 'That's my constitutional right.'