NEW : Police pen student demonstrators in for 6 p.m. , a protester says . Students are angry about government plans to allow tuition increases . She estimated 20,000 to 25,000 people had turned out . A large crowd filled the street near Parliament in Birmingham . Other protests are reported in Cambridge , Leeds and Cambridge .
NEW : Police pen student demonstrators in for 6 p.m. , a protester says . Students are angry about government plans to allow tuition increases . A large crowd filled the street near Parliament in Birmingham . Other protests are reported in Cambridge , Leeds and Cambridge .