Six anti-government protesters were killed and dozens of others hurt Tuesday in Sanaa, Yemen, as government troops fired live rounds at crowds, witnesses said. A doctor working at a field hospital used by protesters said the facility received six bodies and that more than 60 people were injured, Gulf News reported. The doctor expected more casualties at hospitals. Witnesses said government forces rounded up protesters who were demanding President Ali Abdullah Saleh\'s resignation. The witnesses said activists organized two marches along different streets to increase pressure on Saleh to leave office. On Sunday, at least seven Yemeni civilians and soldiers died in fighting between forces loyal to Saleh and his rivals, Gulf News reported Monday. One person told Gulf News that Sanaa saw fierce fighting Sunday and Monday between Saleh forces and the 1st Armed Division, led by Gen. Ali Mohsen Al Ahmer, who defected. The division is backed by tribesmen loyal to Sheik Sadeq Al Ahmer and his brothers. \"We were scared stiff when the three-hour shelling started. We could see the shells lighting the sky like meteors,\" the witness said. \"We are waiting for the shells to hit us at any time.\"