Sanaa: Fierce battle erupted in Yemen capital Sanaa on Tuesday as truce that ended deadly clashes last week broke down. 

There were also heavy exchanges between the tribesmen and loyalist troops around the headquarters of the military police and the official Saba news agency, as well as in a major thoroughfare, according to reports.

The government of veteran President Ali Abdullah Saleh accused fighters loyal to Sheikh al-Ahmar of breaking the truce which was announced on Friday and went into force on Sunday.

The defence ministry's news website said that his tribesmen had seized both the headquarters of the ruling General People's Congress and the main offices of the water utility.

But sources close to Sheikh al-Ahmar accused Saleh's forces of breaking the truce by firing on his compound in the north of the capital.

A plume of black smoke could be seen billowing into the sky over the area, witnesses said.