At least nine people were killed and 90 others wounded when forces loyal to Yemeni President Ali Abdullah Saleh opened fire Saturday on protesters in the capital Sanaa demanding he face trial, a medical source said.

Mohammed al-Qubati, a doctor at a field hospital that has treated protesters during 11 months of mass demonstrations against Saleh, said about 150 other people were wounded by tear gas canisters troops fired, or incapacitated from inhaling gas.

(Reporting by Mohammed Ghobari; Writing by Joseph Logan)