The family of US journalist Evan Gershkovich said on Wednesday that they have asked the United Nations for assistance in their efforts to free him in Russia, where he was imprisoned in March on spying accusations that carry a maximum sentence of 20 years in prison.

Gershkovich’s parents and sister stated they had submitted a petition to the United Nations Working Group on Arbitrary Detention, standing outside the U.N. Security Council with US Ambassador to the UN Linda Thomas-Greenfield.

“This petition explains that Evan’s detention is a violation of his human rights and that Russia should release him immediately. We just want him home,” Gershkovich’s father, Mikhail, told reporters.

The Working Group has a mandate from the Geneva-based U.N. Human Rights Council to investigate “cases of deprivation of liberty imposed arbitrarily or inconsistently with the international standards” by asking governments to clarify or bring attention to cases.

The United States says Russia is using Wall Street Journal reporter Gershkovich to conduct “hostage diplomacy”, at a time when Moscow’s war in Ukraine has plunged relations with Washington to their lowest point in more than 60 years.

“No family should have to watch their loved one being used as a political pawn,” Thomas-Greenfield told reporters. “That’s exactly what President Putin is doing. Russia’s actions are beyond cruel. And they are a violation of international law.”

Washington says the case against him is bogus and has demanded the release of both Gershkovich and Paul Whelan, a U.S. citizen convicted of espionage in 2020 and serving 16 years in a Russian penal colony on spying charges that he too denies.

Gershkovich was arrested on March 29 in the Urals city of Yekaterinburg. No date has been set for his trial, and late last month his detention in Moscow’s Lefortovo prison was extended by three months to Nov. 30. Gershkovich denies the charges.

“Evan has now been wrongfully detained by Russia for nearly six months for doing his job as a journalist,” Gershkovich’s mother, Ella Milman, told reporters. “We are still in shock. Every day is a day too long, I miss him every day.”