Egypt: Hundreds dead as mosque attackers gun down worshippers

(CNN)At least 235 people were killed and another 109 injured in an attack Friday on a Sufi mosque in Egypt's North Sinai region, Egyptian state-run media reported, in what appears to be the deadliest terror attack on Egyptian soil.

After at least two explosions, gunmen who were waiting outside the mosque opened fire at worshippers as they fled Friday prayers, state-owned Ahram Online said.

The attack targeted al Rawdah mosque between Bir al-Abed and the city of al-Arish. Sufism is a mystical branch of Islam that some ultra-orthodox Muslims consider heretical.

Bodies lie on the floor of al Rawdah mosque following a gun and bomb attack Friday.

Key developments

Coordinated attack: Gunmen fired on people fleeing after explosions took place at the mosque. The attackers also opened fire on ambulances, witnesses said.

The target: The mosque in the northern Sinai is known as the birthplace of an important Sufi cleric.

Egypt's reaction: President Abdel Fattah el-Sisi vowed to respond to the attack with "brute force."

'Ambush' followed blasts

The gunmen had set up "ambush" locations and opened fire on ambulances as they were transporting wounded worshippers from al-Rawdah toward al-Arish before the arrival of security services, eyewitnesses reported.

Photos from inside the mosque showed what appeared to be bodies lined up in rows on the carpet.

In a short, televised speech made after he met with security officials, Sisi vowed to restore security and avenge those killed.

"We will respond to this act with brute force against these terrorists," he said. "This terrorist act will strengthen our resolve, steadfastness and will to stand up to, resist and battle against terrorism."

He added: "Egypt is facing terrorism on behalf of the region and the world."

The presidency has declared three days of national mourning.

Injured people are taken to the hospital after the mosque attack Friday.

The mosque is known for being the birthplace of Sheikh Eid al-Jariri, a Sufi cleric considered the founder of Sufism in the Sinai Peninsula.

The blasts from improvised explosive devices caused considerable damage to the mosque, Ahram Online said.