The government on Monday announced steep price rises for petroleum products after suspending state subsidies as part of crucial economic reforms, sparking demonstrations in central-eastern Sudan.
Anti-riot police fired tear gas to disperse hundreds of demonstrators who took to the streets of Wad Madani, capital of Al-Jazeera state, burning tyres and chanting slogans against the rises, witnesses said.
Oil prices at the pump have shot up to 20.8 Sudanese pounds ($4.71) a gallon from 12.5 pounds ($2.83), while diesel has risen from 8.5 pounds a gallon to 13.9 pounds.
President Omar al-Bashir said Sunday that subsidies on petroleum products had reached "a level that is dangerous for the economy," with inflation now running at 40 percent.
Anti-regime demonstrations spread last year after Bashir announced similar austerity measures including tax hikes and an end to cheap fuel.
The cost of petrol at the pump roughly doubled at that time when fuel subsidies were partly lifted.
In June and July 2012, Arab Spring-inspired rallies, often involving groups of 100 or 200 demonstrators, spread around Sudan and became the longest-running challenge to Bashir who seized power in an Islamist-backed coup 24 years ago.
The protests flickered out after a security crackdown.
Sudan lost billions of dollars in oil receipts when South Sudan gained independence two years ago, taking with it about 75 percent of the formerly united country's crude production.
Since then Sudan has been plagued by inflation, a weakened currency and a severe shortage of dollars to pay for imports.