About 5,000 students have demonstrated in the Kenyan capital, Nairobi, to demand the reinstatement of their union, banned two years ago after the authorities accused it of organising violent marches.

Since Sonu was banned, communication between the students and the university administration has completely broken down Joseph Mbugua, student

Students broke shop windows and robbed passers-by near the university.

Police used tear gas to try to force the students back into their halls of residence, but the demonstration only ended when an education ministry official promised that the ban on the union would be lifted.

This is the first case of social unrest in Kenya since President Mwai Kibaki was elected last month.

'Grievances addressed'

The students said the demonstration was the only way for them to be heard.

"Since Sonu was banned, communication between the students and the university administration has completely broken down," political science student Joseph Mbugua was quoted as saying by the French news agency, AFP.

Some of the students broke into shops and looted, snatched car stereos and robbed passers-by of their mobile phones as they marched through Nairobi.

The police fail to stop the demonstrators

The demonstration fizzled out after the deputy minister for education, Fred Gumo, said that the ban on Sonu would be lifted.

"The vice chancellor has agreed to reinstate the students' union," Mr Gumo told the demonstrators outside the city's main campus.

"All your grievances will be addressed," he said.

They have also demanded that some 300 fellow students expelled for various offences be readmitted to the university.