New | Two New York police officers executed in their squad car in 'revenge killing'

A gunman ambushed and fatally shot two New York City police officers on Saturday and then killed himself, police said, and a social media post indicated it may have been in revenge for the police chokehold death of an unarmed black man.

The officers were killed without warning and at close range as they sat in their squad car in the Bedford-Stuyvesant section of Brooklyn, Police Commissioner William Bratton told a news conference, flanked by New York City Mayor Bill de Blasio.

"Although we’re still learning the details, it’s clear that this was an assassination, that these officers were shot execution-style," said de Blasio.

New York police have come under intense pressure in recent weeks, with protests erupting after a grand jury declined this month to charge a white police officer involved in the chokehold death of Eric Garner during an arrest attempt in July in the borough of Staten Island.

Demonstrations over Garner’s death came on top of protests around the country over another grand jury’s decision in November not to indict a white police officer who fatally shot an unarmed black teenager in Ferguson, Missouri. President Barack Obama, who was briefed on the New York killings while on vacation in Hawaii, has had to calm eruptions of anger over police brutality against minorities.

The killings were the first time New York City police officers have been killed by gunfire since 2011 and were bound to fuel anger among some police against de Blasio, who has had a prickly relationship with law enforcement.