Sudanese security forces fired tear gas Thursday morning at dozens of protesters manning barricades in the capital Khartoum, a witness said.

Police have remained deployed in large numbers in north Khartoum where demonstrators kept up their protests through the night, witnesses said.

Wednesday saw the deadliest crackdown on anti-coup protests since last month’s military takeover.

At least 15 demonstrators were killed in Wednesday’s protests, most of them in north Khartoum, medics said.