The death toll from a bomb and gun attack at a Sufi mosque in Egypt's northern section of Sinai has risen to 305, with 128 injured, CNN reported.

Twenty-seven children were among the dead, Egypt's state prosecutor said Saturday.

Between 25 and 30 armed men carried out the assault on the mosque in Bir al-Abed, the state prosecutor said in a statement. They arrived in five SUVs and were equipped with automatic machine guns. The attackers then took up positions in front of the mosque and its entrances, CNN reported.

No group has claimed responsibility, CNN reported.

Egyptian President Abdel Fattah el-Sisi has vowed to respond to the massacre with “brute force.” On Saturday, Egyptian warplanes conducted airstrikes on "terrorist outposts" and vehicles following the attack, CNN reported.