Seven people were taken into police custody Thursday (June 21) in connection with a series of attacks on Christian sites in Brittany in northwest France, according to French media reports. The detained individuals range in age from 20 to 30 years, but no further details regarding their identities have yet been released.A shadowy anti-religious group with links to heavy metal music has claimed responsibility for the attacks, which included burning down the 16th-century Chapel of the Cross (slideshow) at Loqueffret near the remote tip of Brittany (France). The doors of the chapel were forced open, and several original polychrome statues were destroyed, according to Expatica. Members of the group, which calls itself "True Armorik Black Metal", or TABM, describe themselves as "extremist and anti-ecclesiastical" in a letter sent to local newspaper the Telegramme, which published excerpts on Thursday. "We are going to strike again, again and again," warned the letter, in which the group's acronym is scrawled in blood-red letters over the image of an inverted Christian cross. Graffiti of the letters ABM was found at nine Christian sites desecrated in recent weeks. Police previously believed the letters signified Aryan Black Metal, a Satanist movement which has links to heavy metal music, paganism and far-right politics. Eight other Christian shrines — six roadside granite crosses and two fountains — were torn down or smashed last month in an area of the Finistere department near the popular holiday resorts of Benodet and Concarneau.