Mayor Bill de Blasio said this is 'not the time for politics' following the murder of two police officers in Brooklyn on Saturday.

This as New York City's police commissioner said the gunman who ambushed and killed two police officers had made online posts that were 'very anti-police.'

Police Commissioner William Bratton choked up at a news conference at the Woodhull medical Center on Saturday afternoon as he talked about the fatal shootings of two officers in Brooklyn's Bedford-Stuyvesant neighborhood.

Meanwhile, an eyewitness who spoke to The Daily Beast said that 'a lot of people were clapping and laughing' following the murder of the two police officers.

'Some were saying, "They deserved it," and another was shouting at the cops, "Serves them right because you mistreat people!”'said the man, identified as Carlos.

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Joint conference: Mayor Bill de Blasio (left) and police commissioner William Bratton (right) at a news conference following the murder of two officers on Saturday

Coked up: 'They were quite simply assassinated,' said Bratton (above) of the two officers

Tragedy: Rafael Ramos (left) and Wenjian Liu (right) were murdered in the line of duty

Emotional: A police officer wipes tears away from his face as he walks away from the scene of a shooting

'They were, quite simply, assassinated — targeted for their uniform. ... They were ambushed and murdered,' said Bratton.

'Every New Yorker should feel they were attacked, that our entire city was attacked, by this heinous individual,' said de Blasio.

'When a police officer is murdered it tears at the foundation of our society. It is an attack on all of us.'

De Blasio added; 'Our city is in mourning. Our hearts are heavy. We lost two good men who devoted their lives to protecting all of us.'

Mayor de Blasio and Bratton also talked of meeting with the family of the victims, Wenjian Liu and Rafael Ramos.

Liu was just married, and Ramos has a 13-year-old son.

Hundreds of members of the NYPD turned their back to Mayor de Blasio as he entered the news conference Saturday evening, and later these same officers lined the streets and silently saluted as the bodies of the two slain officers were taken away.

Speaking out: 'Every New Yorker should feel they were attacked, that our entire city was attacked, by this heinous individual,' said de Blasio

Paying tribute: Hundreds of cops line the street outside the hospital before the bodies of the two officers are taken away

The news conference took place at the Woodhull Medical Center (above) in Brooklyn

In a statement Saturday night, Attorney General Eric Holder condemned the shooting deaths as senseless and 'an unspeakable act of barbarism.'

Bratton said the gunman shot and wounded his former girlfriend in Baltimore earlier Saturday and made posts from her Instagram account.

MAYOR BILL DE BLASIO'S NEWS CONFERENCE SPEECH

Our city is in mourning. Our hearts are heavy. We lost two good men who devoted their lives to protecting all of us. Officer Ramos, Officer Liu died in the line of duty, protecting the city they loved. Our hearts go out to their families, to their comrades in arms at the 84 Precinct, to the larger family of the NYPD. We honor the EMTs, the doctors, the nurses, everyone at Woodhull who tried valiantly to save their lives and couldn't. I want to thank everyone who came here today to support these families that are in such pain right now. All the leadership of the NYPD, the elected officials who are here – I thank them for coming here in solidarity with these grieving families and our police department. Although we are still learning the details, it's clear that this was an assassination – that these officers were shot, execution-style – particularly despicable act, which goes at the very heart of our society and our democracy. When a police officer is murdered, it tears at the foundation of our society. It is an attack on all of us. It's an attack on everything we hold dear. We depend on our police to protect us against forces of criminality and evil. They are a foundation of our society, and when they are attacked, it is an attack on the very concept of decency. Therefore, every New Yorker should feel they, too, were attacked. Our entire city was attacked by this heinous individual. Even though the assailant took his own life, we'll be vigilant for any information about anyone else who might be involved. And this is a point to make clear to all my fellow New Yorkers – that any time anyone has information that there might be an attack on our police, there might be an act of violence directed at any police officer, it is imperative that that be reported immediately. You heard the commissioner outline the tragic timeline, but anybody who sees a posting on the internet or any other indication of an intention to attack the police must report it immediately. Call 9-1-1. Report it to a police officer. But whatever the situation, that information must get into the hands of the police immediately, so we can protect the lives of our police officers and, in fact, of all of us, since they protect us. There is a sadness that is very, very hard to describe. Commissioner Bratton has felt it many times. I have felt it many times. We met the family members. We met the parents of Officer Liu, the woman he recently married. We met the wife of Officer Ramos. We met his 13-year-old son, who couldn't comprehend what had happened to his father. And with other public servants, and with leaders of this police department, we prayed over the bodies of these two officers. And I ask that all New Yorkers pray for them, pray for their families. It's a moment of terrible loss and it's a moment when we must all come together to support these families, to support healing, and to be thankful that there are heroes among us, like Officer Ramos and Officer Liu. Advertisement

Authorities didn't get into the specifics of the contents of the posts, but two officials said that he posted about shooting two 'pigs' in retaliation for the death of Eric Garner. They spoke on condition of anonymity because they were not authorized to speak publicly.

Ismaaiyl Abdullah Brinsley, 28, shot his girlfriend in Baltimore on Saturday morning then traveled to Brooklyn, New York City, to kill officers Liu and Ramos before turning the gun on himself.

Liu and Ramos may have not even seen the gunman before they were shot, Bratton said.

Not having it: Hundreds of members of the NYPD turned their back on Mayor de Blasio as he entered the news conference on Saturday

Stand and salute: members of the FDNY honor the two murdered police officers

Hundreds lined the streets of Brooklyn on Saturday night

The family of Michael Brown released a statement condemning the shootings, this after reports the killer had mentioned the name of the murdered teenager on his Instagram early Saturday.

'We reject any kind of violence directed toward members of law enforcement. It cannot be tolerated. We must work together to bring peace to our communities,' they said.

'Our thoughts and prayers go out to the officers’ families during this incredibly difficult time.'

POLICE COMMISSIONER WILLIAM BRATTON'S NEWS CONFERENCE SPEECH

The Mayor and I have just come from visiting with the families of our two murdered police officers. It's a time of great emotion and great passion. And so, please bear with us as we try to bring some sense to the madness that occurred this afternoon in the streets of Brooklyn. It's sometimes difficult to find the words to speak to events like those that occurred today, and try to make sense of them – but we'll try. Today, two of New York's Finest were shot and killed, with no warning, no provocation. They were, quite simply, assassinated – targeted for their uniform, and for the responsibility they embraced to keep the people of this city safe. At approximately 2:47 pm today, Police Office Wenjian Liu and Police Officer Rafael Ramos were assigned to a critical response vehicle – CRVs, as we refer to them – in the confines of the 79 Precinct. While a CRV is traditionally used for counterterrorism operations, this past May, we also assigned some vehicles to housing developments throughout the city – developments that had seen an increase in violence in the early part of the year, like the Tompkins Houses, where the officers were stationed. While sitting in a marked NYPD police car, in full uniform, both were ambushed and murdered in front of 98 Tompkins Avenue in the Bedford-Stuyvesant area of Brooklyn, New York City. Both officers are assigned to the 84 Precinct, but were posted at this location as part of a department crime reduction strategy to address complaints of violence in the area of the housing developments in that area. Officer Ramos was in the driver's seat, and Officer Liu was in the front passenger seat beside him. According to witness statements, the suspect, who has been identified as 28-year-old Ismaaiyl Brinsley, walked up to the police car. He took a shooting stance on the passenger side and fired the weapon – his weapon – several times through the front passenger window, striking both officers in the head. Officer Liu and Officer Ramos never had the opportunity to draw their weapons. They may never have actually even seen their assailant – their murderer. Other officers, who were also assigned to the CRV post, immediately pursued Brinsley southbound on Tompkins Avenue. Brinsley then turned westbound on Myrtle Avenue and fled into the Myrtle Avenue and Willoughby Street – the G train subway station. He proceeded down the stairs onto the westbound subway platform. While on the platform, Brinsley shot himself in the head – took his own life. A silver semi-automatic [inaudible] firearm was recovered on the subway platform near the suspect's body. Officers Liu and Ramos were transported here, to Woodhill – Woodhull Hospital. Despite every effort to save their lives, both officers tragically succumbed to their injuries. On behalf of the New York City Police Department, I extend my deepest condolences to the Liu and the Ramos families, and the families within the NYPD. Both officers paid the ultimate sacrifice today while protecting the communities they serve. The suspect was transported to Brooklyn Hospital, where he was pronounced dead. We are currently continuing to investigate this incident. I want to thank, at this time, Dr. Raju and his trauma staff for their valiant efforts – but unsuccessful efforts – to resuscitate our officers. Some background information relative to the events leading up to the murder of our two officers today – at approximately 5:45 this morning, in Baltimore County, Maryland, a female, believed to be Brinsley's former girlfriend, was shot and seriously wounded by Brinsley at her residence. Baltimore County detectives later received information from the victim's mother that Brinsley was posting on the victim's instagram account. Further information was developed indicating that Brinsley may have had associations with the East Flatbush area of Brooklyn. At approximately 2:45 this afternoon, Baltimore authorities sent a fax – a warning flyer, a wanted flyer – to the NYPD and other agencies. Tragically, this was essentially at the same time as our officers were being ambushed and murdered by Brinsley. Tragically too, this is not the first time this department has seen such violence. Seven times since 1972, we have seen partners murdered together, often in incidents such as this – mindless assassinations without warning. Our officers know this, from memorial walls on our precincts and headquarters, and from the stories they hand down. Nevertheless, they do what we expect of them. They grieve, they mourn, but then they go out on the streets of this city and work to keep it safe, every day and every night. We have never, and never will, forget that mission. We will never forget the two young men who lost their lives today. Advertisement

Governor Andrew Cuomo released a statement Saturday evening saying; 'Tonight, the thoughts and prayers of all New Yorkers are with the family and friends of New York City police officers Wenjian Liu and Rafael Ramos, who were assassinated in the line of duty.

'This deplorable act of violence is the opposite of what New York is and what New Yorkers believe in.

'These brave officers, along with the over 34,000 other uniformed men and women of the New York Police Department, put their lives on the line every day to keep our communities safe.

'They run toward danger when all of our instincts tell us to run away.