Death toll from Syria bomb attack on bus convoy rises to at least 120

The evacuation of more than 3,000 Syrians that was scheduled to take place Sunday from four areas as part of a population transfer has been postponed, opposition activists said, a day after a deadly blast that killed more than 120 people, many of them government supporters.

The reasons for the delay were not immediately clear. It came as shells fired by ISISon government-held parts of the eastern city of Deir el-Zour wounded two members of a Russian media delegation visiting the area, according to state-run Syrian news agency SANA.

Russia is a main backer of Syrian President Bashar Assad and Russian journalists enjoy wide access in government-held parts of the country.

The United Nations is not overseeing the transfer deal, which involves residents of the pro-government villages of Foua and Kfarya and the opposition-held towns of Madaya and Zabadani. All four have been under siege for years, their fate linked through a series of reciprocal agreements that the UNsays have hindered aid deliveries.

Rami Abdurrahman, who heads the Britain-based Syrian Observatory for Human Rights, and Hezbollah's Al-Manar TV said 3,000 people will be evacuated from Foua and Kfarya, while 200, the vast majority of them fighters, will be evacuated from Zabadani and Madaya.

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Abdurrahmansaid Saturday's blast which hit an area where thousands of pro-government evacuees had been waiting for hours killed 126. He said the dead included 109 people fromFouaandKfarya, among them 80 children and 13 women.

No one has claimed the attack, but both the ISISand theal-Qaida-affiliatedFatahal-Sham Front have targeted civilians in government areas in the past.

Children lured to the blast

A wounded girl, who said she lost her siblings in the blast, toldAl-ManarTV from her hospital bed that children who had been deprived of food for years in the two villages were approached by a man in the car who told them to come and eat potato chips. She said once many had gathered, there was an explosion that tore some of the children to pieces.

After the blast, some 60 buses carrying 2,200 people, including 400 opposition fighters, entered areas held by rebels in the northern province of Aleppo,Abdurrahmansaid.

More than 50 buses and 20 ambulances carrying some 5,000FouaandKfaryaresidents entered the government-held city of Aleppo, Syrian state TV said, with some of them later reaching a shelter in the village ofJibreento the south.

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UNreliefco-ordinatorStephen O'Brien said he was "horrified" by the deadly bombing, and that while the UNwas not involved in the transfer it was ready to "scale up our support to evacuees."

He called on all parties to uphold their obligations under international humanitarian and human rights law, and to "facilitate safe and unimpeded access for the UNand its partners to bring life-saving help to those in need."

Residents ofMadayaandZabadani, formerly summer resorts, joined the 2011 uprising against PresidentBasharAssad. Both came under government siege in the ensuing civil war.

Residents ofFouaandKfraya, besieged by the rebels, have lived under a steady hail of rockets and mortars for years, but were supplied with food and medicine through military airdrops.

Evacuations draw criticism

Critics say the string of evacuations, which could see some 30,000 people moved across battle lines over the next 60 days, amounts to forced displacement along political and sectarian lines.

In eastern Syria, anairstrikeby the U.S.-led coalition on the village ofSukkarieh,near the border with Iraq, killed eight civilians who had earlier fled violence in the northern province of Aleppo, according toDeirEzzor24, an activist collective, and Sound and Picture Organization, which documents ISIS violations.

Airstrikesby the U.S.-led coalition had killed dozens of civilians over the past several weeks as the battle against the extremists intensifies in Syria and Iraq.

U.S. may not send more troops

U.S. President Donald Trump's national security adviser is expressing doubt the U.S. will send more ground troops to Syria. His comments come as rebel forces appear close to launching an assault to capture the Islamic State group's de facto capital of Raqqa.

H.R. McMaster spoke to ABC's "This Week" from Afghanistan. He says it "remains to be seen" whether additional troops are needed, but he doesn't "think so." McMaster says the U.S. will support its "partner forces" in Syria.

The U.S. has been expected to provide additional arms to the U.S.-backed Syrian Democratic Forces for the Raqqa offensive. But it hasn't been clear about troops.

Last week, Trump appeared to rule out deeper American military intervention in Syria beyond retaliatory strikes if Syria's president continued to attack civilians with chemical weapons.

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