Newly emerged before and after pictures of the monkey sent by Iran into orbit have suggested that country's 'much-boasted' space mission was fake, a report has said.
Footage on state television before the mission showed a grey primate wearing a mini space suit and strapped into a pod.
However, video of the animal astronaut being welcomed home appears to show he'd lost a distinctive mole and tufts of white hair had turned brown.
According to the Daily Mirror, this also fuelled further speculation that the capsule never returned to Earth, or that it did but the monkey did not survive.
The US State Department even expressed doubts about whether the rocket launch even happened at all, the report said.
Iran's defence ministry had proclaimed the launch "a giant step" in space technology "which is the monopoly of a few countries".
Its ambitious aerospace programme, which aims to have a man in space by 2020, includes plans for a space centre.
A similar space monkey mission in 2011 failed, although authorities refused to give any reason.