A GARDA INVESTIGATION is underway after a major fire broke out at an all-girls secondary school in Dundalk overnight.

The fire broke out at about 3am last night at the St Louis Secondary School on Castletown Road.

A number of fire brigade units attended the scene and the fire was extinguished. The crews remain at the scene of the fire which is being preserved.

No injuries were reported following the blaze despite extensive flames being visible in a video posted by local radio station LMFM.

Writing on its Facebook page this morning, the school thanked the fire crews from Dundalk and Ardee who attended the scene for their “wonderful work”.

A statement from the school said:

We would like to say a huge thank you to the fire departments of Dundalk and Ardee under Officer Paul Kelly for their wonderful work in the early hours to ensure that there was minimal damage to our beautiful school. They managed to contain the fire. Parents we will keep you updated via text. The main building was not damaged by the fire and we are thankful that no one was hurt.

Gardaí have said that investigations into the fire are ongoing.

Reacting to the overnight blaze, Louth TD Gerry Adams said that the fire was “troubling”.

“The cause of the fire is not yet known but three fire engines are still at the scene. I commend the fire fighters,” Adams said.

“This is exam time so I hope that damage is not too extensive and that pupils can return to school as soon as possible.”