Gardaí have charged a 30-year-old man with the rape of two young girls in Athlone on Saturday.
The man, who cannot be named for legal reasons, will appear at a sitting of a district court in the morning.
More than 150 people gathered outside Athlone Garda Station this evening.
Senior garda officers came out of the building to ask the crowd to disperse.
Two other men who were being questioned have been released without charge.
A file is being prepared for the Director of Public Prosecutions.
The girls, aged six and nine, were hospitalised after the incident and are expected to be interviewed by gardaí in the coming days.
Officers are using the services of a specialist interviewer to try to find out what happened to the two children on Saturday afternoon.
The girls were outside a house at a birthday party in a busy residential area at 4pm when they were asked to accompany a man they did not know to another building nearby.
After being lured inside, they were detained in a room where they were seriously assaulted.
The alarm was raised when they returned to the party a short time later.
An immediate attempt was made to forcefully apprehend a man inside the house where the assault took place.
Earlier, a group of people gathered outside the courthouse in Athlone to show support for the families of the young children.