Sudanese security forces have fired tear gas at thousands of angry demonstrators who were protesting against President Omar Hassan al-Bashir.

The demonstrations -- on their sixth consecutive day -- were held as people buried the protesters who were shot dead in recent violence.

Thousands of angry protesters marched on the main roads in the south of capital, Khartoum, and hurled stones at passing-by cars. A large number of police personnel responded by firing tear gas and rubber bullets.

Anti-government protests first erupted over fuel price hikes and the government's slashing of fuel and cooking gas subsidies.

As the government tried to break up the rallies in the south of Khartoum, they spread to other parts of the country including Nyala, the capital of the restive state of South Darfur.

Human rights groups say security forces have killed at least 50 people. Sudanese police put the death toll at 33 and blame unknown gunmen for the killings.

Sudan lost billions of dollars in oil revenues after South Sudan gained independence two years ago, taking with it some 75 percent of crude oil production of the formerly united country.

The country has been plagued by running inflation and a weakening currency since then.

The Sudanese government is trying to restore peace to violence-hit regions. Sudan’s Education Ministry announced that schools in the capital would remain closed until the end of the month.