Pope Francis waves from the popemobile in Ciudad Juarez, Chihuahua state, Mexico on February 17, 2016.
March 6, 2016 10:40 AM EST

Pope Francis said Sunday that the four nuns who were killed in a “diabolical” attack at a retirement home in Yemen were martyrs who “gave their blood for the Church.

The pontiff expressed his grief for the 16 people who were murdered Friday after gunmen stormed the charity, which was established by Mother Teresa, handcuffing their victims before shooting them in the head, the Associated Press reports.

Pope Francis said those killed were both victims of the attackers as well as victims of “this indifference of globalization.” The condolences came as an al-Qaeda umbrella group denied responsibility for the killing spree, CNN reports.


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