Transport Minister Anrijs Matiss told the BNS news agency that anti-corruption officers also conducted a search at Magonis’ office on Thursday.
With events moving fast, an extraordinary meeting of Latvijas Dzelzcels shareholders was called on Friday to dismiss Magonis as head of the railway company, a decision they made by 11 am, appointing Aivars Straksas, a member of the Latvijas Dzelzcels management board, as acting chairman.
The move was confirmed in a brief statement on the Transport Ministry website.
"The Ministry of Transport held an extraordinary shareholders' meeting, which decided to release from office the current Joint Stock Company Latvian Railways Chairman of the Board Uģis Magone.
"Also the extraordinary shareholders' meeting decided to appoint board member Aivars Strakšas."
Matiss said that the Transport Ministry has been fully cooperating with the anti-corruption bureau but that he had no information about the reasons for Magonis’ detention.
Laura Dusa, a representative of the Corruption Prevention and Combating Bureau, told BNS that information about Magonis’ detention would be provided later.
Magonis did not answer telephone calls on Friday morning.
Magonis has worked at Latvian Railways since 2003, and as president since 2005. Magonis has been chairing the Latvijas Dzelzcels management board since 2005. From 2003 to 2005 he was chairman of the Latvijas Dzelzcels supervisory board.
Latvijas Dzelzcels is a state-owned company, involved in freight transportation by rail and the maintenance of infrastructure.
It is a key strategic player in the economy, responsible for huge transit volumes to and from Russia as well as employing around 12,000 people.
As previously reported by LSM, Magonis previously made headlines for holding a lavish birthday party at Rundale Palace to which he invited - among others - Russian Railways Vladimir Yakunin, a close associate of President Vladimir Putin who is blacklisted by the US but who was removed from an EU blacklist after lobbying from Latvia.
The party included huge projections of Magonis' smiling face on the UNESCO-listed walls in a display of hubris likely to be absent on Friday.
In 2013 he was awarded a state decoration, the 'Cross of Recognition' (motto: “Pour les honnêtes gens”/"For Honest People") by President Andris Berzins.