 The usurpation of Magnentius and his defeat in 353 may have further increased troubles in Britannia.Attacks on the province took place in 360 and, some years later, secret agents, known as the Areani (or 'Arcani'), operating between Hadrian's Wall and the Vallum as intelligence-gatherers, were involved in the Great Conspiracy of 367–368.They were accused of going over to the enemies of the empire, such as the Picts, the Scotti (from Ireland), and the Saxons, in return for bribes and the promise of plunder.