BEIRUT (AP) -- A large explosion rocked a camp for displaced Syrians along the Syrian-Jordanian border Saturday, killing at least six, and wounding many others, opposition activists said.
The explosion near the border came despite the fragile Dec. 30 cease-fire, sponsored by Russia and Turkey who back opposite sides of the conflict. Syria continues to be beset by violence, including clashes between government forces and rebel fighters as well as a number of offensives against Islamic State militants in the country.
Talks between government officials, rebel representatives and attended by Russian, Turkish and U.N. officials are scheduled Monday in the Kazakh capital, Astana, to discuss reinforcing the cease-fire and ensuring humanitarian access.
Some rebel factions have agreed to send representatives, but the al-Qaida-linked Fatah al-Sham Front slammed the talks Saturday as a "conspiracy." In a statement, the front said that any rebel group attending the Astana conference would be essentially agreeing that Syrian President Bashar Assad will stay in office. The government and Russia insist that the Islamic State group and the Fatah al-Sham Front must both be excluded from any cease-fire.
Fatah al-Sham, one of the most powerful on the ground on Syria, said other rebel factions had been pressured by their foreign patrons to attend and that the end result would be to drive a wedge between Syria's insurgents. Rivalries have plagued Syria's insurgents. Infighting as well as splits and failed mergers have been reported in recent weeks- further weakening their ranks.
"Negotiations in Astana about the fate of the country and its people are not the right of one side," the group said in a statement. "Those who risk the battlefield and bypass must realize the consequences in the future."
Near the border with Jordan, Mohammed Hassan al-Homsi, an opposition activist with the Palmyra News Network, said a small truck carrying blankets was detonated from afar, killing at least six civilians at the Rukban camp, including a man, his wife and two children.
Badr Abu Sultan, a resident of the Rukban camp, said the explosion occurred outside the local market. "There was a powerful explosion at the beginning of the market," Abu Sultan, a member of a tribal council in the camp, said.
The Britain-based Syrian Observatory for Human Rights said the explosion caused a huge cloud of smoke over the area. A video posted by the Syrian Media Organization also showed some tents burning, as parts of the car bomb were scattered across the camp. The Observatory, which has a network of activists on the ground, put the death toll at 11, including the family of four, and four militiamen. Another opposition activist network, the Palmyra Coordination group, said the explosion hit a checkpoint for a local militia near the market.
The camp houses a local militia targeted in the past by rival factions in Syria's war.
A Jordanian military official ruled out any Jordanian was hurt in the explosion inside Syrian territory. He told the official Jordanian Petra news agency 14 wounded were admitted to the Jordanian health center at the border used to treat Syrians.
Jordan has been on edge since a car bomb attack last year launched from Rukban killed seven Jordanian border guards. Jordan then sealed the border, cutting off vital aid to 75,000 Syrians stranded in the area.
The displaced Syrians live in makeshift camps between two parallel earthen barriers, or berms, that mark the Jordanian-Syrian frontier.
Meanwhile on Saturday, The Russian military said that six of its long-range bombers have struck Islamic State positions in Deir el-Zour in eastern Syria. The raid came as Syrian government troops in Deir el-Zour found themselves in an increasingly difficult situation, cut in half in an ongoing IS offensive against the last remaining pockets of government control.
The extremist group controls most of the province, except for the provincial capital and a nearby air base, and the offensive which began earlier this month is described as the group's most intense in a year.
The Russian Defense Ministry said that six Tu-22M3 bombers flew from their base in Russia to strike IS facilities Deir el-Zour province on Saturday. It said they successfully hit all designated targets, including the militants' camps, weapons locations and ammunition depots.
Activists in Deir el-Zour say amid intense shelling from Russian, Syrian and coalition jets and fighting on the ground, civilians are fleeing.
Russian fighter jets from Hemeimeem air base in Syria's coastal province of Latakia provided cover for the bombers, according to the ministry.
Russia has conducted an air campaign in Syria since September 2015, helping Syrian government forces to reverse the tide of the nearly six-year conflict.
Associated Press writers Dominique Soguel in Istanbul, Maamoun Youssef in Cairo and Vladimir Isachenkov in Moscow contributed to this report.