Ismaaiyl Brinsley, the lone gunman identified as the shooter of 2 NYPD police officers, bragged about his intentions to give “pigs their wings” on social media.

The Baltimore resident, who allegedly killed the officers to avenge the deaths of Eric Garner and Michael Brown, reportedly shot his girlfriend early Saturday before traveling to Brooklyn, where he snuck up on a police car and shot two officers “execution” style in the head. After the shooting, he allegedly walked to a subway station, where he turned the gun on himself.

A police source told the New York Post the killings resembled “an execution,” with the shooter “pumping bullets” into the officers.

According to International Business Times, Brinsley posted on Instagram, Twitter and Facebook before and after the shooting, but the accounts have since been removed.

Before the accounts were removed, people were able to get screenshots of the disturbing posts.

“I’m Putting Wings On Pigs Today,” Brinsley posted on Instagram under the moniker DontRunUp. “They Take 1 Of Ours… Let’s Take 2 of Theirs #ShootThePolice #RIPErivGardner #RIPMikeBrown… This May Be My Final Post. I’m Putting Pigs In A Blanket.”

NYPD confirms shooter who killed 2 cops shot girlfriend then posted on Instagram that he was going to kill NYPD cops. pic.twitter.com/J1nZ9RIU5R

— New York City Alerts (@NYCityAlerts) December 21, 2014

NYPD Commissioner William Bratton confirmed Brinsley was linked to a shooting in Baltimore County, Maryland, according to the New York Times.

Maryland officials, who were made aware of the social media posting against the NYPD, notified New York, but it was too late — the officers were being shot at the time the NYPD received the notice.

NEW: FB of "Ismaaiyl Brinsley" confirms IG acct "dontrunup" days ago: "Why live if you don't love to live" 11hrs ago pic.twitter.com/bqLA9YAPn8

— Kenny Holmes (@KHOLMESlive) December 21, 2014

Bratton said there was no indication Brinsley had any accomplices.

A man who claims to be a friend of Brinsley, Paul Young, told the Daily Mail the alleged shooter is a rapper who was very involved in the anti-police protests.

Attorney General Eric Holder deemed the shooting deaths of two New York City police officers “cowardly” and an “unspeakable act of barbarism,” according to the Associated Press.

President Obama “has been briefed on the Brooklyn police shooting” and “officials continue to monitor the situation,” according to a White House press release.