WASHINGTON (AP) — Republican presidential candidate Chris Christie says the Black Lives Matter movement is creating an environment that can put police officers at risk. And he’s accusing President Barack Obama of supporting the movement and encouraging “lawlessness” while not backing up law enforcement.

The New Jersey governor says on Sunday said, “I don’t believe that movement should be justified when they are calling for the murder of police officers.” Speaking on CBS’ “Face the Nation,” Christie said Black Lives Matter is “creating” an environment, as some of its supporters have chanted for the death of police.

The movement organized after the 2012 shooting of Trayvon Martin, an unarmed teen, by a neighborhood watch enthusiast.

Obama last week defended Black Lives Matter, urging the nation to take police treatment of black Americans seriously.

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