MANILA, Philippines (AP) — Officials say the death toll in a brazen road attack by Abu Sayyaf extremists on some 50 villagers traveling in the southern Philippines to celebrate the end of Ramadan with their families has climbed to 23 after a 3-year-old boy and his father died from their injuries.

Marine Brig. Gen. Martin Pinto said Tuesday six villagers remain in the hospital following the militants’ bloodiest attack in recent years.

About 40 to 50 Abu Sayyaf militants armed with assault rifles opened fire Monday on the group traveling in two vans in a coastal village in Talipao town in predominantly Muslim Sulu province, where the extremists have survived in jungle camps despite years of U.S.-backed Philippine military offensives.

Pinto says the pursuit operations against the militants were continuing.