More than 100 MPs have signed a letter to President Barack Obama calling on him to stop the extradition of an autistic British man accused of hacking into US computers.
Lauri Love, 31, is alleged to have stolen huge amounts of data from US agencies including the Federal Reserve, the US Army, the Department of Defence, Nasa and the FBI, in a spate of online attacks in 2012 and 2013.
US authorities have been fighting for Reverend's son Mr Love to face trial over cyber-hacking charges that his lawyers say could mean a sentence of up to 99 years in prison if he is found guilty.
The letter signed by 105 cross-party backbenchers expressed their "deep concern for the safety" of Mr Love, citing his "long history of serious mental health issues, depression and some episodes of psychosis".
Mr Love, who also suffers from depression and severe eczema, lives with his parents near Newmarket in Suffolk.
His father, Reverend Alexander Love, has said he fears a jail term in the US would cause his health to deteriorate and would lead to a mental breakdown or suicide.
The case echoes that of Gary McKinnon, another alleged cyber-hacker with Asperger's, who eventually had his extradition blocked by then home secretary Theresa May after a decade-long battle.
The MPs point out the UK has prosecuted at least 12 people who have hacked US-based computer systems.
The MPs said the US legal pursuit of Mr Love would make him "the first UK-based computer hacker to be extradited and denied the opportunity to face a full prosecution" in the UK.