The Greenmount Restaurant next door to the Cycle and Trophy Centre was also damaged as a result of the blaze at the north end of Clanbrassil Street on Sunday week last.
Five units of Louth Local Authority fire service had been fighting the blaze at the cycle shop from 11am that morning.
That blaze was under control by Sunday afternoon, but at 8.30pm fire units had to return to the scene.
They then had to return at midnight when it was discovered that embers from the cycle shop blaze had reached the roof of the Greenmount restaurant next door.
This blaze was brought under control but the building was also badly damaged.
Louth Local Authority engineers sealed off the street in front of both premises.
Traffic remains diverted from the Square to the centre of Clanbrassil Street, down Market Street, Chapel Street, St Mary’s Road, to the other side of the damaged buildings at York Street.
Traffic can then turn at the traffic lights opposite the Green Church and round to the Demesne and the Long Walk. This brings all traffic back to the Adelphi or traffic can proceed north.