The U.N. Security Council is condemning "in the strongest possible terms" the bombing in Iran that killed 27 people, calling it a "heinous and cowardly terrorist attack."

All 15 members, including the United States, which is a strong critic of Iran's leaders, "expressed their deepest sympathy and condolences to the families of the victims and to the government of Islamic Republic of Iran."

The al-Qaida-linked group Jaish al-Adl claimed responsibility for Wednesday's suicide car bombing that struck a bus carrying soldiers of Iran's Revolutionary Guard in the restive southeastern province of Sistan and Baluchistan.

The Security Council's statement Thursday says terrorism threatens international peace. It says the attack underlines "the need to hold perpetrators, organizers, financiers and sponsors of these reprehensible acts of terrorism accountable and bring them to justice."