ADEN, Yemen, March 6 (UPI) -- An Indian priest remains missing in Yemen in the wake of a deadly attack on a nursing home that left 16 dead.
On Sunday, officials said they believe the attack was perpetrated by the Islamic State and the group is holding the priest, Tom Uzhunnalil, captive. Indian officials promised a comprehensive rescue mission.
"Yemen is a conflict zone. We do not have Embassy there. But we will spare no efforts to rescue Father Tom Uzhunnalil," External Affairs Minister Sushma Swaraj wrote in a tweet.
On Friday, a group of militants stormed an elder care home in Yemen's port city of Aden. The home is run by Mother Teresa's Missionaries of Charity. After killing a Yemeni guard, the gunmen reportedly tied up and killed 16 residents, including four nuns.
Pope Francis condemned the attacks on Sunday, referring to the victims of the "pointless slaughter" as "martyrs" in a statement released by the Vatican.
Some early reports blamed Ansar al-Sharia, a local branch of al Qaeda, for the attacks. But the group quickly denied responsibility.
"Our honorable people of Aden, we Ansar al-Sharia deny any connection or relation to the operation that targeted the elders' house," the terror group said in a statement. "This is not our operation and it's not our way of fight."
The IS, also known as ISIS, ISIL and Daesh, has yet to claim responsibility for the attack, but Yemeni security officials believe the attackers are affiliates of the Iraq and Syria-based terror organization.