The 51-year-old man was detained on Friday after attending a seminar on digitalization in the Norwegian parliament last week. He was placed in custody for two weeks on espionage charges after a court hearing and reportedly faces three years behind bars.

The Russian Embassy in Norway has denounced the detention of a Russian national at an Oslo airport on suspicion of illegal intelligence activities.

“We believe the detention and subsequent arrest are far-fetched and done under an absurd pretext,” the Russian embassy wrote on Facebook.

The detained Russian national has taken part in several seminars across Europe in recent years, the Norwegian public broadcaster NRK reported.

The seminar hosts said they had alerted Norway’s police security service PST after observing “strange behavior” from the unnamed participant. They identified him as a “chief adviser in the Russian parliament” in 2012 who gave a lecture on mobile applications and wireless networks to the Federation Council the following year, NRK said.

The broadcaster cites the national police security service PST as warning that intelligence officers specifically use open seminars and conferences on security policy, technology and innovation to establish contacts.

“He doesn’t understand the charges and believes this is all due to a misunderstanding,” the suspect’s lawyer Hege Akre was quoted as saying.

In comments to Norway’s VG tabloid, Akre said his client has “good explanations” to clarify what aroused the seminar hosts’ suspicions.

Reuters contributed reporting to this article.