Sudanese police fired teargas to disperse some 400 demonstrators who marched through Sennar to protest a hike in bread prices, eyewitnesses told Reuters.
There were no immediate reports of deaths or injuries.
Bread prices in Sudan doubled since government eliminated subsidies last week under its 2018 budget.
The price of a loaf of bread rose from 0.5 Sudanese pounds (seven cents) to a pound, the Bakeries Union said after the prices of wheat flour rose.
“We were protesting against the rise in bread prices and we call on the government to scrap it,” said a protestor in Sennar, south of Khartoum.
“We can’t afford to buy a piece of bread for a whole pound,” said the demonstrator, who did not want to give his name.
The ministry of interior could not be reached for comment.
The country’s main opposition parties called for peaceful protests against the price hikes and crowds gathered outside bakeries in Khartoum, expressing frustration at government’s move.
Sudan’s government started a series of economic reforms in line with International Monetary Fund recommendations aimed at putting the country’s ailing economy back on track.
The economy has been struggling since the south seceded in 2011, taking with it three-quarters of the country’s oil output, its main source of foreign currency and government income.
The Sudanese pound has weakened since October after the United States lifted a 20-year-old trade embargo, prompting businesses to increase import volumes, putting pressure on already scarce foreign currency.
The country devalued its currency to 18 per US dollar, more than double its previous peg of 6.7 pounds to the dollar.