A Romanian court has ruled that an investigation into the 1989 revolution where 1,104 people died can be reopened.

Romania has been criticized for failing to investigate the revolution, where mainly unarmed demonstrators were shot dead around Romania from Dec. 17-30 as they protested against Communist leader Nicolae Ceausescu.

In October 2015, the prosecutor general's office said the investigation into the revolution had been classified. Caretaker prosecutor general Bogdan Licu called the classification "unfounded and illegal," and said the file should be reopened to find out what happened.

The High Court of Cassation and Justice on Monday formally ruled to allow the investigation to reopen.

Many former communists retained their positions in the justice system and politics after the regime fell, and there was reluctance to investigate what happened.