MANAMA, Bahrain — A bombing outside a mosque near the royal palaces has rattled Bahrain, prompting authorities and main opposition groups in the violence-wracked Gulf kingdom to denounce the attack.

No one was injured in the blast, which struck late Wednesday in the mosque parking lot during evening prayers. But it was a rare explosion near the site of the royal residences, pointing to widening attacks by militant factions as part of the 29-month unrest.

Bahrain's majority Shiites are seeking a greater political voice in the strategic Sunni-ruled nation, home to the U.S. Navy's 5th Fleet.

The recent rise in bombings suggests breakaway militant factions now operate outside the main Shiite political blocs.

The largest Shiite political group Al Wefaq "condemned" the attack on Thursday. Security officials called it a "terrorist" act.