Heavy gunfire was heard at a protest outside the defence ministry in Sudan's capital Khartoum on Tuesday, live broadcast by Arab TV stations showed, and activists said that security forces were trying to break up the protest by force.

Activists said in a statement posted on social media that army soldiers guarding the ministry were trying to protect the demonstrators and opened the gates of the compound to give sanctuary.

Both Al-Hadath TV and Al Jazeera broadcast live footage in which heavy gunfire was heard and people were seen running for cover. They said it was an attempt by security forces to disperse the demonstrators.

There were reports that at least two government soldiers were killed, but it was not immediately possible to verify.

Sudan has been rocked by months of small but persistent protests that were sparked by bread price rises and cash shortages. The demonstrations later turned against President Omar al-Bashir, a former paratrooper who had been in office since 1989.