The United Nations has confirmed that an armed group has detained 43 of its peacekeeper forces by the Golan Heights' Quneitra crossing, which was overrun by Islamist rebel fighters in Syria after months of fighting with troops loyal to President Bashar al-Assad.

A statement from the UN also said that 81 peacekeepers "are currently being restricted on their positions in the vicinity of Ar Ruwayhinah and Burayqah" on the Israeli-Syrian border.

"The United Nations is making every effort to secure the release of the detained peacekeepers, and to restore the full freedom of movement of the force throughout its area of operation," the statement read.

Earlier, unconfirmed reports stated that at least 50 troops from the Philippines serving in the region were kidnapped by militants of the al-Qaida-linked al-Nusra front.

Fighters affiliated to the Islamist group, along with other militants, attacked the Quneitra crossing early on Wednesday and managed to hold the ground despite heavy fire.

Islamist forces are reportedly within 200 yards of territory controlled by Israel. The IDF (Israel Defense Forces) said one soldier was wounded by "errant fire" from the clashes at the crossing.