Police raided a number of Unite's offices as part of a major bribery, fraud and money laundering investigation.
It is understood police in unmarked cars arrived at a number of the union's offices with a warrant on Wednesday, April 7. MirrorOnline reports police left with files, documents and a computer relating to one specific employee, who the union has said is now part of a criminal probe.
South Wales Police, which is leading the investigation alongside HMRC, said warrants were executed across the country, including in Cheshire and Merseyside.