Four members of an Iranian separatist group, the Arab Struggle Movement for the Liberation of Ahwaz, have been arrested in Denmark and the Netherlands. Three were arrested Monday in Ringsted, 40 miles southwest of Copenhagen, for the suspected spying of people and companies for an unnamed Saudi intelligence service over a period of six years from 2012. Another was arrested in the historic Dutch city of Delft for allegedly plotting one or more terror attacks in Iran and for membership of a terrorist organisation. "We are talking about a very complex case where two countries — Iran and Saudi Arabia — are bringing internal strife into this country,” Danish security service chief Finn Borch Andersen said. The three members of the London-based group who were arrested in Denmark could face a pre-trial custody hearing Tuesday in Roskilde, 25 miles west of Copenhagen. If found guilty, they face a potential life sentence, which in Denmark is on average 16 years. No further details of those arrested, including their sex or age, were disclosed. Borch Andersen said the arrests in Denmark were linked to a case in the Netherlands where police arrested a 40-year-old man. Dutch police said that part of the ASMLA movement has an armed wing that carries out attacks in Iran, mainly against the Iranian Revolutionary Guard as well as oil and gas fields. The arrests are also said to be linked to a 2018 police operation over an alleged Iranian plot to kill one or more opponents of the Iranian government. The operation briefly cut off the island on which Copenhagen sits from the rest of Denmark. An unnamed Norwegian citizen of Iranian descent was arrested in Oct. 2018 on suspicion of helping an unspecified Iranian intelligence service "to act in Denmark" and of alleged involvement in the assassination plot. That suspect has denied wrongdoing and is being held in pre-trial custody. Tehran has accused ASMLA for an attack on a military parade in the Iranian city of Ahvaz in September 2018, that left at least 25 people dead. The group has condemned the violence and said it was not involved. Borch Andersen also said a member of an Iranian intelligence agency who is not in Denmark, was jailed in absentia for being the handler of the Norwegian citizen. No further details were available.