A third man has been arrested in connection with an arson attack on a house in Longford last night in which an 11-year-old girl sustained burns.

Gardaí arrested the man, who is in his 20s, tonight in Longford Town. He has been taken to Roscommon Garda Station, where he is being questioned.

Two other men, one arrested shortly after the attack and another this afternoon, remain in custody at Longford Garda Station.

The young girl who was injured in the fire is said to be in a stable condition following the fire on the Pauric Colum Heights estate.

A family of five people was in the house when it was set alight shortly before midnight.

The house was engulfed in flames when emergency services arrived at the scene.

The family has been living in the estate for more than 20 years.

Ann Joyce, the mother of the injured girl, today described how she pleaded with the culprits not to throw petrol bombs into her home.

She said she begged with one of the masked men and told him that young babies were sleeping in the house.

She said one of the five occupants of the house jumped from an upstairs window to escape the blaze and another sustained burns as he ran through the house as it was engulfed in flames.

The attack is believed to be linked to an ongoing feud between two families and follows incidents in recent weeks in Clara, Co Offaly, and Drogheda, Co Louth.

Gardaí are treating the incident as extremely serious and an investigation is under way, with a forensic examination of the scene to take place today.

Anyone with information is being asked to contact gardaí in Longford on 043-3350570.