A 13th century monastery in the monastic community of Mount Athos in northern Greece caught on fire late on Tuesday, causing damage worth an estimated 50,000 euros but no injuries, authorities said yesterday. The blaze, which broke out at about 10 p.m., burned 60 square meters of the Koutloumousiou Monastery’s roof and floor space. Authorities said that the fire damaged some furniture but was contained before it could threaten ancient manuscripts or other valuable items. It was not immediately clear what had started the blaze. The monastery, sixth in the hierarchy of 20 in the all-male Orthodox Christian sanctuary, has suffered repeated fire damage over the years, including as recently as 1980.