(CNN) -- Sudanese police fired tear gas on a hundred university students demonstrating against government austerity measures and calling for the president's ouster Sunday, a journalist in Khartoum, Sudan, reported.
The government ordered a crackdown on protests that began a week ago and grew in size and number in the last several days, the journalist, who asked not to be identified, told CNN Sunday.
"I was told a good number of activists have been detained from their homes before they even join the protest as a precautionary measure," the reporter said.
Growing numbers of protesters have rallied in the capital against government spending cuts and other measures. The protests have in some cases turned violent, with people throwing stones at police, burning tires and police trucks, and cutting off roads.
Police have been ordered to take harsh measure against any protests, including the use of tear gas, the reporter said.
Women and children, who joined the students in the streets, have not been spared the tear gas except in the case of older women, the journalist said.
Students at two Khartoum universities were in the streets protesting Sunday, but several other demonstrations were taking place elsewhere, the reporter said.
The head of Sudan's police force told his officers Saturday how to deal with riots, groups targeting property, and arbitrary road closures by protesters "in accordance with the laws," state television reported.
At the same meeting with Gen. Hashim Osman Hussein, police called on residents of Khartoum to "cooperate with the police in doing its job to enforce the law aimed at securing the homeland and its citizens," state TV reported.
After Friday prayers, crowds called for the toppling of President Omar al-Bashir.
"Leave, Bashir, leave!" they chanted. "Khartoum, people, please revolt against humiliation and dictatorship."
Police and security agents intensified their crackdown Saturday, detaining a number of opposition figures and surrounding the buildings of two of the country's main opposition parties.
Officers used batons to disperse the demonstrations and police vehicles patrolled throughout the capital.
In a televised speech on state media last week, al-Bashir urged citizens to understand the new harsh austerity measures, which lifted fuel subsidies and cut the Cabinet by half to reduce expenses.
Sudan has faced soaring inflation since it separated with South Sudan a year ago -- taking with it more than 70% of Sudan's oil reserves.
The nation's inflation has gone up by 30%, according to Sudanese Finance Minister Ali Mahmud.
Protesters have vowed to hold mass rallies June 30, when the ruling party celebrates 24 years in power. Organizers are also calling for mass action using social media sites such as Twitter and Facebook, where they are posting pictures and details of upcoming protests.
The government has described the week-long protests as small and urged citizens to avoid them. Government officials were not immediately available for comment.
In similar protests in January last year, students vowed to replicate the Arab Spring that has swept over the Middle East.