Iran's announcement that it had successfully sent a monkey into space stirred questions on the Internet on Saturday, with people pointing to differences between official images of the primate before takeoff and after landing.

On January 28, official Iranian media published pictures of a monkey named Pishgam (Pioneer) prior to the launch. The animal had light grey fur and a red mole above its right eye.

But later, the ISNA news agency released photos taken during presenting the monkey to the press after its landing which showed a darker fur and no mole.

These differences have been pointed out by Western media, which have questioned the success of the monkey space mission. A previous attempt to send a primate into space failed in 2011.

On Facebook, a comment underneath the monkey's pictures reads: the monkey "went into space and met a doctor who removed its mole," an ironic reference to some Iranians passion for cosmetic surgery.

Iranian authorities did not directly responded to these questions on Saturday night.

Two websites close to the regime, Rajanews and Nasimonline, have said without citing sources that the monkey images available to the media before the launch were "archive" images of the doomed 2011 launch.

Instead, the monkey presented to the press after the sub-orbital flight was the one that successfully completed the mission.

Neither Iranian site gave any explanation why the reputed archive pictures were used by the media.