This tweet about the Planned Parenthood shooting sums up another sad truth about America

In news that is achingly familiar to the US, last night it emerged that a gunman entered a Planned Parenthood clinic in Colorado and managed to kill three people.

The attack has unfortunately given rise to a vicious backlash from some pro-lifers, who have celebrated the deaths as justified.

Police confirmed the identity of the suspect as Robert L. Dear, who was arrested at the scene.

Civil rights activist Deray McKesson watched the story unfold, noting as he did so that after the stand-off with police which led to the death of one officer, Dear was escorted from the scene in handcuffs.

But as McKesson wrote on Twitter, there are countless examples of black people in the US, including children, being shot at by police for far less.

Just this week, authorities in Chicago released video footage which showed a police officer needlessly gunning down 17-year-old Laquan McDonald, who was shot 16 times as he walked away from a police officer last year.

President Barack Obama has once again called for Congress to act on stricter gun controls.

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