Four explosions hit the government controlled cities of Tartous, Homs and in the countryside outside the capital Damascus, while a fifth explosion hit the Kurdish-held city of Hasaka.

It is not immediately clear whether there is any link between the blasts in the state-held cities, or whether they had been coordinated with the attack in Hasaka.

There has been no immediate claim of responsibility for the blasts, which all took place between 8am and 9am local time.

The UK-based Syrian Observatory for Human Rights, which maintains a network of contacts inside the country, put the death toll at 24.

Two violent explosions hit the Arzouna bridge area at the entrance to the northwestern coastal city of Tartous, the Observatory and state news agency Sana said.

At least 11 people were killed and 45 wounded, a source in the Tartous police told Sana.

Syrian state television said the first explosion was a car bomb and the second was a suicide belt detonated as rescue workers came to the scene of the first incident.

A car bomb struck the city of Homs at the entrance to the Bab Tadmur neighbourhood, Sana said.

The governor of Homs province said a car bomb struck a military checkpoint in the provincial capital, Homs, killing two soldiers and injuring four others, one critically.

A motor bike exploded in the centre of the northeastern city of Hasaka, which is under the control of the Kurdish YPG militia.

The Observatory said the blast killed three members of the Kurdish security force, known as the Asayish, and two civilians.

Sana also reported an explosion in the Sabbourah suburb in the capital Damacus, killing one. The Observatory said three were killed.

Isis claimed twin suicide bombings that killed over 160 people in the neighbouring coastal towns of Tartus and Jableh in May.

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