Isolation and harsh conditions at Guantanamo Bay have driven a Syrian prisoner to attempt suicide, repeatedly bang his head against the wall and show other signs of "mental deterioration," his lawyers alleged Friday as they sought an emergency court order to improve his conditions.

Mohammed Khan Tumani, who like his father has been held at Guantanamo without charge for seven years, should be moved to a less restrictive section of the prison and be given an independent medical examination, his lawyers said in a motion filed in a federal court in Washington...