In a high-profile snub captured on mobile phone video, a line of uniformed officers turned silently to face the corridor walls rather than look at the mayor who some claim has betrayed them.
The two officers, Wenjian Liu and Rafael Ramos, were shot dead execution-style on Saturday by Ismaaiyl Brinsley, a repeat criminal offender who had vowed on social media postings to avenge the deaths of Eric Garner and Michael Brown, two unarmed black men killed in encounters with police.
Reports were also emerging on Sunday lunchtime of a third officer being shot dead in a residential district of Florida, in circumstances that are as yet unclear.
Many police are furious that Mr de Blasio has backed protestors who have staged anti-police protests in the wake of decisions by grand juries in New York and Missouri not to prosecute white officers for the deaths of unarmed black men.
The New York Post, a conservative tabloid that has backed police union criticisms of Mr de Blasio, reported an earlier icy exchange at the Brooklyn hospital. “We’re all in this together,” the mayor reportedly told a group of police. “No, we’re not,” an officer replied tersely, according to the account.
The back-turning snub was co-ordinated by police union chiefs who took part in the protests and have been scathing in their criticism of the mayor for his comments on law enforcement and race relations.
“There’s blood on many hands tonight,” said Patrick Lynch, the leader of the largest police union, the Patrolmen’s Benevolent Association. “That blood starts… on the steps of City Hall, in the office of the mayor.”
Ed Mullins, the president of the sergeants’ association, used similarly inflammatory language.
“Mayor de Blasio, the blood of these two officers is clearly on your hands,” he said. “It is your failed policies and actions that enabled this tragedy to occur. I only hope and pray that more of these ambushes and executions do not happen again.”
They were speaking shortly after a deeply-emotional scene as hundreds of officers stood to salute or with their hands over their hearts while the bodies of the two men were driven away from the hospital.
Even before the killings, the PBA had urged the mayor to stay away from funerals of police officers killed in line of duty, issuing members with a waiver to sign entitled “Don’t Insult My Sacrifice”.
Bill Bratton, the city’s police chief, rebuked the union for that stance and Mr de Blasio accused the PBA of “playing politics”. No plans for the funerals have been announced yet.
After the shooting of the two officers on Saturday, Brinsley ran into a local subway station and shot himself in the head as armed officers closed in.
Earlier in the day, he had shot and wounded his former girlfriend at Owings Mill, about 15 miles from Baltimore, before making his way to New York.
At the same time police in Baltimore issued an alert to forces about Brinsley, which was received by NYPD as he was killing the two officers in Brooklyn.
Police were studying social media after discovering Brinsley had boasted of his plans to murder officers on his former girlfriend's Instagram account in revenge for the killing of two black men, Eric Garner and Michael Brown, by police earlier this year.
The post, which was put on the Internet three hours before the shooting, showed a picture of an automatic handgun and a pair of camouflage trousers matching those which were worn by the gunman.
According to the New York Daily News he wrote: "I’m Putting Wings On Pigs Today. They Take 1 Of Ours ... Let’s Take 2 of Theirs.”
