Sudan arrested its former spy chief and other senior military and security officers on Thursday after foiling what officials said was a plot to incite chaos and target leaders in this oil-producing African state.
Witnesses told Reuters they saw army tanks and armored vehicles moving down a main street in the tightly-controlled center of Khartoum around midnight, but the city appeared normal by the morning.
Sudan's President Omar Hassan al-Bashir has kept up a near 25-year hold on power, even as a series of uprisings troubled the country's poor border areas, including the conflict-torn region of Darfur.
But Sudan has been stuck in economic crisis since the south — the source of most of its known oil-reserves — declared independence last year under the terms of a peace deal.
High prices for food and other basics have added to widespread public anger over losing the south and have emboldened opposition activists to call for protests. Analysts say the crisis has also exacerbated divisions in the government.
Unrest over price rises and food and fuel shortages has preceded coups to overthrow the government in Sudan in the past.
Salah Gosh, former head of Sudan's powerful intelligence and security agency, was arrested with others on suspicion of "inciting chaos," "targeting" some leaders and spreading rumors about Bashir's health, the information minister told reporters.
"Thirteen people were arrested," the minister, Ahmed Belal Osman, said. "The situation is now totally stable."
Tanks headed downtown
Witnesses said they saw military vehicles on a major street that runs alongside the city's airport overnight.
"We saw something unusual in Khartoum … four armored vehicles and two tanks on Abeid Khatim Street heading in the direction of downtown," one witness said, asking not to be named.
Sudan's security and intelligence agency "foiled a sabotage plot this morning aimed at bringing about security disturbances in the country led by figures from the opposition forces," the state-linked Sudanese Media Center reported earlier on Thursday.
Quoting a security source, the media center said authorities arrested "military and civilian figures" in connection with the plot.
Security at the defense ministry, intelligence headquarters and other buildings associated with military and security authorities appeared normal early in the morning, a Reuters witness in the city said.
Sudan has been plagued by political conflicts and crises for most of its history since independence from Britain in 1956.
Decades of civil war between the north and south culminated with South Sudan's independence in July last year under a 2005 peace deal.
Tensions in both nations and between the two states have been high since then. The two countries accused one another of incursions in disputed border zones on Wednesday, a setback to recent security and border deals.
Small demonstrations against cuts in fuel subsidies and other austerity measures broke out across Sudan in June but petered out after a security crackdown and the start of the Muslim fasting month of Ramadan.