1.   About three dozen protesters, clad in black, did turn up at the rally, some wearing masks and carrying shields.

2.   The group was met within minutes by military police clad in riot gear and carrying shields.

3.   Officer in riot gear and carrying plastic shields to fend off debris and rocks tried to contain the violence by barricading streets.

4.   Police threw a security cordon around the facility and prison officers dressed in riot gear and carrying perspex shields were called in.

5.   Prison intervention police, clad in riot gear and carrying protective shields, were called in to deal with the prisoners, who were throwing tables and chairs.

6.   Some members of the crowd tore up paving stones to throw at police, who were carrying shields and other anti-riot equipment, witnesses said.