BURSTS of shelling threatened a fragile new truce in Yemen's capital Sanaa late Tuesday as politicians scrambled to end the bloodiest fighting in eight months of anti-government protests.

Both government forces and troops loyal to General Ali Mohsen, who defected to pro-democracy protesters in March, vowed to stand by a ceasefire ordered by Vice President Abd-Rabbu Mansour Hadi.

But witnesses said two mortars hit the end of a street Tuesday evening where thousands of protesters were camping out to demand an end to President Ali Abdullah Saleh's 33-year rule.

The death toll has risen to around 70 since Sunday, when protesters' frustration boiled over at Saleh's refusal to accept a mediated handover plan. Saleh has been in Saudi Arabia since June, where he had surgery on injuries that he suffered in an assassination attempt.

The fighting between state troops and defected soldiers began after tens of thousands of protesters marched Sunday close to a part of Sanaa controlled by government forces.

(SD-Agencies)