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The family of Trevor Reed, a US citizen detained in Russia, met US President Joe Biden, who restated his commitment to secure the release of the Marine Corps veteran and other detained Americans, White House Press Secretary Jen Psaki said.
Mr Reed has been held in Russia since 2019, and was sentenced to nine years in prison by a Moscow court in 2020 for endangering the "life and health" of Russian law enforcement officials in an altercation, the Russian news agency reported at the time.
White House Press Secretary
Joey and Paula Reed protested in front of the White House on Wednesday to raise awareness of their son's case. The protest came as Trevor initiated a second hunger strike in protest against his treatment by Russian authorities, according to a statement posted on Twitter.
"President Biden met today with Joey and Paula Reed, the parents of Trevor Reed, who is wrongfully detained in Russia," Ms Psaki said on Wednesday night.
"We understand the pain felt by all of Trevor’s families and friends enduring the nightmare of his absence, which we are committed to bringing to an end."
Mr Reed began his first hunger strike on November 4, claiming he had been placed in isolation for allegedly breaking prison rules. He has denied any wrongdoing.
"Trevor's Mordovian lawyer was able to see him [on Tuesday] and confirmed that Trevor began a hunger strike ... to protest against] being sent back to solitary while injured and having TB [tuberculosis]," his parents said in the statement.
"Soon after he returned, Trevor asked authorities at the IK-12 gulag to return to the hospital. Instead, authorities returned him to solitary confinement."
They said: "Again, while we are in awe of our son's integrity and strength of character, as his parents, there aren't words to express how concerned we are about our son's health."
This was the second time Mr Biden had spoken to the parents, having previously spoken to them by phone on March 8 when he was in Texas.
Mr Biden said he is also committed to releasing Paul Whelan and other Americans "wrongfully held in Russia and elsewhere".
Mr Whelan was sentenced to 16 years in prison in 2020 on espionage charges that his family and the US claim are false.

Meanwhile, State Department spokesman Ned Price said US diplomats are being denied access to Americans held in Russia, including basketball star Brittney Griner.
The Olympic gold medallist was detained after arriving at a Moscow airport in mid-February and is currently being held on narcotics charges.
The WNBA said it is working with the US government to free Griner after a state-run Russian media outlet said her detention has been extended until May 19.
Agence France-Presse contributed to this report.