Both Pope Francis and the World Council of Churches head on Easter Sunday called for Christians to work and pray for those who can bring about peace to end the carnage in the seven year Syrian civil war.

The Pope used his Easter Sunday message to denounce the "latest vile attack" on Syrian civilians, in which at least 126 were believed killed, more than half of them children, as thousands gathered at the Vatican's St. Peter's Square to hear him speak.

"Especially in these days, may he [God] sustain the efforts of all those actively engaged in bringing comfort and relief to the civil population in Syria, prey to a war that continues to sow horror and death," said Francis.

"May he grant peace to the entire Middle East, beginning with the Holy Land, as well as in Iraq and Yemen."

URBI ET ORBI

The pontiff did not specifically mention specific governments, but offered his support for those that "work for justice and peace," in his "urbi et orbi," or "city to the world" traditional address from the balcony at St. Peter's.

"In the complex and often dramatic situations of today's world, may the Risen Lord guide the steps of all those who work for justice and peace," he said.

"May he grant the leaders of nations the courage they need to prevent the spread of conflicts and put a halt to the arms trade."

The World Council of Churches strongly condemns the car bomb attack on the Syrian evacuees on 15th April.

"This continuing infernal cycle of such extreme violence underlines yet again the urgent need for practical progress towards peace in Syria to end the bloodshed," said WCC general secretary Rev. Olav Fykse Tveit on hearing of the attack.

"We call upon all involved governments and armed groups to put an immediate end to all use of deadly force and to support and engage with a political process for peace in Syria, for the future of the country and all its people," said Tveit.

The death toll from a bomb attack on a crowded bus convoy outside Aleppo reached at least 126 in the deadliest such incident in Syria in almost a year, the Syrian Observatory for Human Rights monitoring group said on April 16, Reuters news agency reported.

The bomb detonated in a convoy of coaches carrying evacuees from besieged government-held towns in Syria, wreaking a massive toll.

The blast occurred in the Rashidin area on the outskirts of Aleppo, where up to 70 buses carrying mostly Shi'ite residents of towns evacuated under an exchange deal between the warring sides were waiting to enter the city.

The BBC said the exchange under the "Four Towns" deal was brokered by Iran and Qatar and was meant to relieve suffering in besieged towns - Foah and Kefraya in the north-west which are under government control, and opposition-held Madaya and Zabadani, near Damascus.

"The WCC expresses its deep sympathy to the families of the victims, and prays that God may grant them comfort and heal their wounds," said Tveit.

"We also pray for the God of justice and peace to accompany the Syrian people in these critical and painful moments."

"And I call on all Christians and all people of faith around the world to join together in renewed prayer for peace and an end to conflict and bloodshed in Syria," Tveit added.

Thousands of evacuees have been stranded in hostile territory since the transfers began on April 14. Now those being moved from other besieged areas fear revenge attacks.

About 20,000 besieged people were to have been evacuated. Up to 5,000 government evacuees and 2,200 from rebel towns were stranded in transit on Sunday, AFP news agency reported.

Last month, the UN described the situation in the besieged towns as "catastrophic". More than 64,000 civilians are "trapped in a cycle of daily violence and deprivation", it said.