Cllr Tierney condemned those responsible and has urged anyone with information to come forward to the police.
He said:v“At around 2.30am this morning a family was awoken after a concrete block was thrown through their window in the Fergleen Park area of the city.
“This was a thuggish and cowardly attack carried out under the cover of darkness designed to terrorise a people in our city.
“The family have now been forced to leave their home out of fear for their safety.
“I have been working with them throughout today to secure alternative accomodation.
“I would appeal to anyone who saw or heard anything suspicious in the area this morning to come forward to police.
“Those responsible for this attack need to be caught and should face justice,” he added.