Syria's internet and phone service has resumed in the war-torn nation after a two-day blackout left much of the country cut off.

The blackout, which ended on Wednesday, was blamed by state media on a technical fault, but activists and a watchdog accused the regime of deliberating cutting the connection to shield military operations.

Communication networks had been crucial for opposition activists trying to get out videos and information on the two-year conflict that has killed more than 70,000 people.

Data from Google, Akamai Technologies and Renesys, a US firm that tracks global web traffic, showed that internet traffic started flowing to and from Syria shortly 1400 GMT on Wednesday, after stopping just before 1900 GMT on Tuesday.

"Everything looks the same as before the internet came down," said Jim Cowie, chief technology officer at Renesys.

Syrian state news agency SANA quoted the director general of the General Establishment for Communications, Bakr Bakr, as saying internet services and communication between provinces had gone down because of a malfunction in an optic cable.

'Security operation'

But the Syrian Observatory for Human Rights, a British-based group that monitors President Bashar al-Assad's security forces and the rebels, cited military sources who said that the blackout was part of a security force operation.

Assad's forces have often shut down telephone and internet connections in some cities or neighbourhoods during major combat operations.

Opposition activists alleged they did the same during alleged massacres that killed hundreds of people.

Most recently, communications appeared to have been cut in the coastal towns of Banias and Baida during what activists said were widespread executions that killed hundreds of people, including dozens of children.

The latest outage demonstrated the fragile nature of global internet connections.

In Syria, the system of internet providers is centralised, meaning a single point of failure could bring down all connections, Cowie said.