Heavy gunfire erupted in the Sudanese capital on Tuesday at two bases of the country's feared security agency, witnesses said.
Shooting broke out at the National Intelligence and Security Service (NISS) bases in the upscale Riyadh district and in Khartoum North, witnesses said.
A correspondent for AFP reported that gunfire at the Riyadh base, not far from Khartoum airport, was heavy and steady.
Masked members of the NISS dressed in military uniform set up checkpoints near the Riyadh base and were seen firing shots into the air, one of the witnesses said.
All streets leading to the two bases were cordoned off by security forces, causing traffic jams. At least two flights have turned away from Khartoum following the clashes.
Emirates flight 733 becomes the second aircraft to turn away from Khartoum after heavy clashes started in the city this afternoon.
Shortly after the gunfire began, the NISS announced it had sacked some employees who were unhappy with the severance package they were offered.
A statement by the service did not mention the gunfire, but a security source told Reuters negotiations were taking place to try to resolve the problem.
The Sudanese Professionals Association (SPA), the country's main protest group, called on state agencies to intervene immediately to stop "these irresponsible operations that are causing terror amongst citizens".
Unverified video footage posted on social media purporting to show the area featured the sound of gunfire, Reuters said.
Sudan is undergoing a three-year political transition overseen by civilians and the military following the overthrow of long-time ruler Omar al-Bashir in April.
Security agents of the NISS were at the forefront of cracking down on protesters during the nationwide uprising that first erupted against Bashir in December 2018.
The army ousted Bashir in April last year, and the country's new authorities have vowed to reform the NISS./MEE