MIAMI (AP) — The acquittal of Sanford neighborhood watch volunteer George Zimmerman in the death of 17-year old Trayvon Martin has “deeply saddened” the mayor of Philadelphia.

Mayor Michael Nutter said in a statement Sunday that he strongly disagreed with Saturday night’s verdict in the trial of Zimmerman in the death of the Miami Gardens teen. Zimmerman said he acted in self-defense.

Nutter said “a young black man is dead without any real explanation” and he believes jurors “should have exacted a penalty.”

A month after the February 2012 shooting, Nutter called Martin’s death “nothing short of an assassination.”

Nutter said he was praying for Martin’s family. He also called for efforts to eliminate conditions that lead to the slayings of black males in “outrageously alarming numbers” across the country.

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