Hundreds of landless Brazilian farm workers have stormed a congressional building in the capital, Brasilia.

Officials said about 500 people were arrested and more than 25 hurt,one seriously, in the violence.

It is thought the protesters belong to a splinter group of Brazil's main landless workers group, the Landless Rural Workers' Movement (MST). This splinter group, (MLST) is thought of as "a militant offshoot of Brazil's main landless movement" Their activists smashed windows, tables and doors, overturned a car and clashed with police and security guards.

They even managed to overrun the lower house of Brazil's Congress in Brasilia. Reaching as far as the two main debating chambers where a parliamentary session was taking place, before being forced back

The demonstrators said they had entered the building to demand an end to what they called slave labour and changes to Brazil's legislation to speed up land reform.

They said they had planned a peaceful protest but the police had attacked them.

The farm workers have traditionally backed the ruling party which strongly supports land reform.

But the government has come in for criticism for doing too little to accelerate the process.

When he was elected in 2003, President Lula promised to buy disused land and redistribute it to poor families with no home of their own.

But the MST says the government has failed to live up to its election promises to find homes for 400,000 families by 2006.