Hyperdiction
Hyperdiction is when an Unknown Ship interdicts another ship while traveling through hyperspace. The ship gets pulled out of hyperspace into a system and is temporarily disabled. This occurs in a higher-dimensional region in which travel between star systems is possible at superluminal speeds (many times the speed of light).
Hyperdiction occurs around the Pleiades Nebula and the Maia system. The player does not need to have an unknown artefact in their cargo hold to be hyperdicted.
Humans currently only possess technology to interdict others in Supercruise.