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Gunmen burst into a home, handcuffed people, then shot them in the head, Vatican says

Pope "prays that this pointless slaughter will awaken consciences" and spur peace talks

Yemen has been beset by violence for years, with U.N. estimating up to 2,800 civilian deaths

CNN  — 

Pope Francis prayed Sunday for the victims of a brutal attack that killed 16 people at a home for the elderly in Yemen founded by Mother Teresa.

And now, a home for the elderly run by Catholic missionaries is among them.

The Vatican on Saturday reported the killing of four Missionaries of Charity members plus 12 others at an elderly facility in the port city of Aden.

According to an official Vatican News report, gunmen burst into the building Friday, went room to room handcuffing victims, then shot all 16 in the head.

Aden is on Yemen's southern coast, across the Gulf of Aden from Somalia.

Agenzia Fides, an information service for Catholic missionaries, reported the missionaries – who belonged to the group founded by Mother Teresa – were nuns. Two were from Rwanda, one from India and the fourth from Kenya.

The attack – characterized by Vatican Secretary of State Pietro Parolin as an “act of senseless and diabolical violence” – spurred a sharp rebuke from Pope Francis.

According to Parolin, the Pope “prays that this pointless slaughter will awaken consciences, lead to a change of heart and inspire all parties to lay down their arms and take up the path of dialogue.”

Months of violence

The impoverished Muslim nation has faced violence for years, some of it tied to al Qaeda elements that call it home.

The latest round of unrest started in 2014 amid angry protests by Houthis, a minority Shiite group that’s long held sway in northern Yemen, but hasn’t had much influence in the Sunni-led government.

The Houthi rebels seized the presidential palace in January last year, forcing out President Abdu Rabu Mansour Hadi on the way to taking over Sanaa, the capital city, and other areas.

But Hadi returned, aided by warplanes from Saudi Arabia, the United Arab Emirates, Kuwait, Bahrain, Qatar and others that joined to battle Houthis last March.

Those strikes have continued months later, as has the bloodshed.

The fighting is taking a “terrible toll” on Yemenis, said spokesman Rupert Colville for the U.N. high commissioner for human rights.