Yemen: 37 killed in Sanaa clashes

Violence escalated after a ceasefire broke down between security forces and fighters loyal to Sheikh Sadiq al-Ahmar, head of a tribal confederation.

Analysts say the conflict threatens to drag Yemen into civil war.

Yemen is facing increasing unrest in several areas after President Ali Abdullah Saleh refused to step down.

Witnesses reported heavy fighting in the capital overnight as both sides blamed each other for breaking the ceasefire.

On Wednesday morning, witnesses also reported loud explosions coming from the north of Sanaa, but the reason was not clear.

The defence ministry accused tribesmen of seizing the headquarters of the ruling General People's Congress and other offices in Sanaa.

However, sources close to Sheikh Ahmar said government forces had attacked his compound in the north of the city; Kazinform cites BBC News.

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