It's been over 21 months since American hikers Shane Bauer, Joshua Fattal and the since-released-on-bail Sarah Shourd were detained in Iran on espionage charges. And now they will have to wait longer still for a verdict to be reached in their spying trial: it's been postponed without explanation.

On Wednesday, the lawyer for the Americans, Masoud Shafii, said that his clients were not brought to the courtroom. He was also informed by Iranian authorities that the trial had been postponed. No further information was apparently given. A week ago, Sarah Shourd--currently in the U.S. after being released for poor health--announced she would not be returning for the trial, citing post-traumatic stress disorder.

The families of the hikers have released this statement about the latest troubling development:

"We do not yet know why Shane and Josh were not brought to court but we are even more deeply concerned for their health and welfare as a result of their non-appearance...Their unexplained absence from the hearing, and the fact that their lawyer Mr. Masoud Shafii continues to be denied access to Shane and Josh, is extremely troubling."