Militant groups have been accused of hijacking a massive student demonstration in Ireland that was marred by violence.
Three protesters were arrested after about 50 forced their way into the lobby of the Department of Finance in Dublin city centre angry at proposals to re-introduce fees.
Bricks, bottles, eggs and placards were hurled at gardai in riot gear and on horseback as several hundred people broke off from the main protest.
One Garda suffered a suspected broken nose, one protester was carried from the building apparently unconscious and several others had bloodied noses and heads after the clear-out was ordered.
The Union of Students of Ireland (USI), which organised the main demonstration, distanced itself from the trouble, claiming the march had been a peaceful protest.
Gary Redmond, USI president, said: "The organisation is deeply disappointed at the destructive behaviour of a minority of people at the Department of Finance, which occurred separately from the USI march."
"We do not condone destructive behaviour and believe that peaceful protest and open discussion and debate is the way forward for the students of Ireland."
Gardai estimated 16,000 students marched through the Irish capital to vent their anger over proposed fee hikes which could double annual costs.
More than 200 buses carried students from college campuses nationwide to the USI march, with student representatives putting the number taking part in the rally at Government Buildings at over 40,000.