FILE PHOTO: A printer is marked with a handwritten sign reading “DO NOT USE!!” in parliament in Oslo, Norway, on Sept. 24, 2018, after the arrest of Russian Mikhail Bochkaryov on suspicion of espionage. REUTERS/Nerijus Adomaitis/File Photo

OSLO (Reuters) - Norwegian authorities released a Russian man from jail on Friday after holding him for nearly a month on suspicion of spying.

Mikhail Bochkaryov was detained on Sept. 21 at Oslo airport as he was about to leave the country after attending an international seminar on digitalisation in Norway’s parliament.

He had denied wrongdoing and the Russian Foreign Ministry had demanded that Norway drop the charges and release Bochkaryov, who it identified as a member of staff in the Russian parliament’s upper house.

Norway’s Police Security Service (PST) had sought to extend his detention, but the Oslo District Court on Thursday rejected the request. The PST appealed, but withdrew the appeal on Friday.

“We continue to investigate the case. No decision has been made on whether to file any charges,” PST prosecutor Kathrine Tonstad told Norway’s TV2 news channel. “He is free to go home.”

The case prompted authorities to briefly take several printers out of service near the seminar venue in parliament, and to seal off the foreign affairs and defence committee’s meeting room, one floor below.

Bochkaryov told reporters he was “feeling better now than before his release” when he left Oslo prison on Friday.

The Russian embassy in Oslo said he was staying there and planning to fly to Moscow on Saturday. It expected “an official apology” from Norway for detaining him, it said on its Facebook page.