Sudan’s army deployed around its Khartoum headquarters Monday as thousands of protesters urging the military to join calls for leader Omar al-Bashir’s resignation defied tear gas to demonstrate for a third day, witnesses said.

Since protests erupted across Sudan in December agents of the powerful National Intelligence and Security Service (NISS) and riot police have cracked down on demonstrators, but the army has not intervened.

Protesters have since Saturday camped out around the army complex — which also houses Bashir’s residence and the defence ministry — in the biggest anti-government demonstrations for months.

Witnesses said soldiers were putting up barricades in streets near the compound after NISS personnel and police failed to dislodge the demonstrators.