Gregory Korte

USA TODAY

WARSAW — President Obama urged police and citizens to work harder to eliminate racial bias in policing, saying, "all of us as Americans should be troubled" by the videotaped police shootings of black men this week.

"When people say black lives matter, that doesn’t mean that blue lives don't matter. All lives matter," Obama told reporters upon arriving in Warsaw Friday morning for a two-day meeting of NATO leaders. "This isn't a matter of us comparing the value of lives. This is about us recognizing the burden that's been placed on a particular group of our citizens."

It was an extraordinary statement about a domestic issue as he touched down on foreign soil, delivered in slow and measured tones. Obama said he felt compelled to address the shootings in a televised statement — in addition to a Facebook post published five hours earlier — given the "extraordinary interest" in the incidents.

Obama said he couldn't comment on the details of specific cases, in part because the Department of Justice has opened an investigation into a police shooting in Baton Rouge. There, eyewitness video captured the police shooting of 37-year-old Alton Sterling outside a convenience store Tuesday.

In an unrelated shooting captured on video Wednesday, 32-year-old Philando Castile was shot by police in Falcon Heights, Minn., during a traffic stop while reaching for his driver's license. FBI Director James Comey told Congress on Thursday that he expects a federal investigation of that incident as well.

Both men were black, and Obama said their cases illustrate racial disparities in the criminal justice system and the resulting lack of trust that exists between law enforcement in minority communities. He rattled off a series of statistics to back up his point: Minorities are 30% more likely than whites to be pulled over, three times more likely to be searched and twice as likely to be shot by police, he said.

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"These are not isolated incidents," Obama said. He called for more police departments to adopt bias-free policing policies recommended by a task force he convened last year in response to previous shootings.

But as he's done with similar incidents in the past, Obama took pains to acknowledge the difficult job police officers have. "They’ve got a dangerous job. It is a tough job. And as I've said before, they have a right to go home to their families, just like anyone else," he said.

"There are biases — some conscious and some unconscious — that need to be rooted out. That is not an attack on law enforcement. That's a reflection of the values that the vast majority of law enforcement officers bring to the job."

In an earlier Facebook post published as he was aboard Air Force One, Obama occasionally used even stronger language: "All Americans should recognize the anger, frustration, and grief that so many Americans are feeling — feelings that are being expressed in peaceful protests and vigils. Michelle and I share those feelings," Obama said.