A Russian man detained in Latvia for spying for Moscow has died in prison due to sudden health problems, the Baltic country’s prison administration said on Wednesday, AFP reported, citing news.ro.

53-year-old Ihor Bobirs was detained in August on suspicion of working for the FSB, Russia’s federal security service.

According to the colony’s administration, he died a week ago, after being hospitalized. He died after a “rapid deterioration in general health”.

The Latvian police began an investigation into his death, ordering an autopsy and toxicological examinations.

Igor Bobirs and three other suspects were arrested in August after their names were mentioned in the spying trial of former Latvian interior minister Janis Adamsons.

Janis Adamsons, a former Soviet soldier and later Latvian interior minister in 1994-95, served as a member of the Riga parliament for six terms until his arrest in 2021. In early November, he was sentenced to 8 and a half years in prison for spying for the FSB. A co-accused in this trial, Russian citizen Gennady Silonov, a Soviet-era KGB officer, was sentenced to 7 and a half years in prison for collecting information provided by Janis Adamsons.

Latvia, a former Soviet republic that is now a member of the European Union and NATO, has strained relations with Moscow because of its strong support for Ukraine.