Philippine peacekeepers at one UN encampment were attacked, but those at another were "extricated," Defense Secretary Voltaire Gazmin told reporters in a series of text messages, adding that the attack started early Saturday Syrian time.
Philippine military spokesman Lt. Col. Ramon Zagala told reporters, "There is an ongoing firefight, but all Filipinos are safe."
There were 40 Filipino troops in the encampment that came under attack, and 35 in the second, according to the Philippine military.
The Western-backed militants seized 44 Fijian peacekeepers on Thursday. The militants then demanded that the 75 Filipinos manning two separate UN encampments 4 kilometers (2.5 miles) apart surrender their weapons, but they refused.
The situation of the peacekeepers, whose mission monitors a 1974 disengagement accord between Syria and the Israeli-occupied lands of Palestine, remains "very, very fluid," the UN secretary-general's spokesman, Stephane Dujarric, told reporters Friday at the UN headquarters in New York.
The UN said in a statement that it had received assurances from credible sources that the Fijian peacekeepers "are safe and in good health."
In Australia on Saturday, Australian Foreign Minister Julie Bishop condemned the detention of the Fijian peacekeepers and called for their release.
"As a member of the UN Security Council, Australia demands the unconditional and immediate release of all the detained United Nations peacekeepers," Bishop said in a statement.
Bishop said she telephoned Fijian Prime Minister Voreqe Bainimarama and Foreign Minister Ratu Inoke Kubuabola to express Australia's strong support, including Australia's intelligence resources.
Bishop also said she assured them that Australia will use its position on the UN Security Council to maintain focus on this issue.
Syria sank into war in March 2011 when pro-reform protests turned into a massive insurgency following the intervention of Western and regional states.
The unrest, which took in terrorist groups from across Europe, the Middle East and North Africa, has transpired as one of the bloodiest conflicts in recent history.
SHI/SHI