Anti-government protestors chant slogans during a demonstration demanding the resignation of Yemeni President Ali Abdullah Saleh, in Sanaa,Yemen, Tuesday, March 29, 2011. (AP Photo/Muhammed Muheisen)

Sanaa, Yemen (AP) - Hundreds of thousands of Yemenis are pressing their demand for the country's longtime ruler to step down.

Wednesday's crowds in the capital Sanaa and elsewhere are also denouncing a deadly munitions factory blast that killed at least 100 people in the country's south.

There are also rallies in Saada, where Shiite rebels have fought President Ali Abdullah Saleh's forces for years, and in Marib, an al-Qaida stronghold and one of several areas where the central government has little authority.

The Interior Ministry says at least 100 people were killed and 80 injured in Monday's explosion at the factory in Abyan province, where al-Qaida has been also active.

Opposition groups accuse Saleh of being behind the explosion to create chaos in the country and cling to power.

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