Double car bombings killed at least 57 people and wounded more than 200 people in the Zahra district of Homs on Sunday morning, according to the Britain-based Syrian Observatory for Human Rights.

Later, at least 62 people were killed in a series of attacks near the Shiite shrine of Sayyida Zeinab south of the capital, according to the Observatory.

Attacks at the shrine included a car bombing and two suicide blasts, which ripped through the area. 

But reports claim the shrine itself remained undamaged.

In Homs, graphic footage from pro-Assad television channels showed charred corpses buried among rubble, damage to shop fronts and debris littering a wide area. Many cars were on fire, sending out plumes of black smoke. Wounded people walked around dazed.

ISIS claimed responsiblity for the attack, saying in an online statement that two of its members had driven explosives-laden cars into crowds of residents. 

The Observatory said the attack was the second most deadly of its kind in Homs since 2011, and the deadliest for almost a year and a half.

Once dubbed the capital of the Syrian revolution, Homs city is now almost completely controlled by the Syrian government.

The only exception is Waer district, which is being gradually turned over to the government under a deal with opposition fighters.

Most of the bombing attacks in the city over the past months have been claimed by ISIS, which controls parts of the Homs province including the historic town of Palmyra. 

Zahra neighbourhood in particular has been the main target of the extremist groups as civilian residents there are mostly Alawites, the minority sect of Syria's ruling clan - including president Bashar al-Assad.  

Last month, another twin bombing in Zahra killed 22 people, mostly civilians. 

The double blast comes a day after government forces reportedly captured 31 villages in the northern province of Aleppo from ISIS. 

Syrian troops have been on the offensive in different parts of the country under the cover of Russian airstrikes.

The latest attacks come as US secretary of State John Kerry said that a 'provisional agreement' had been reached with Russia on the terms of a ceasefire in the war-torn country. 

He said the cease-fire could begin in the next few days, but he acknowledged that it has not been finalised and not parties might not automatically comply.    

Kerry told reporters in the Jordanian capital Amman that he had spoken with Russian counterpart Sergei Lavrov again on Sunday on the terms of a ceasefire agreed by world powers earlier this month.

'We have reached a provisional agreement, in principle, on the terms of the cessation of hostilities that could begin in the coming days,' Kerry said.

'It is not yet done and I anticipate that our presidents, President (Barack) Obama and President (Vladimir) Putin, may well speak somewhere in the next days or so in order to try to complete this task,' Kerry told a press conference with Jordanian counterpart Nasser Judeh.

Hopes for ceasefire, which had been due to take hold on Friday, had floundered as fresh violence shook Syria last week.

But Kerry was optimistic that it could still be implemented.

'We are in fact making progress even as a I stand here today,' he said. 'We are closer to a ceasefire today than we have been.'

(www.dailymail.co.uk/news/article-3456948/ISIS-suspected-carrying-twin-car-bomb-blasts-Syria-kill-46-wound-100-one-civil-war-s-deadliest-attacks-yet.html#ixzz40yKKMPRi)