Morocco's king has revoked a controversial royal pardon to a convicted Spanish paedophile, who reportedly is an Iraqi recruited by the Spanish security services as a spy.

The release of Daniel Fino Galvan, 64, after serving only two of a 30 year prison sentence for the rape of children aged between 3 and 15, spareked mass protests in Rabat.

King Mohammed VI said the "exceptional reversal" was made "considering the flaws that marred the process, the gravity of the crimes committed and with respect to the rights of the victims."

The King said he would not have pardoned the Spaniard if he had been aware of his crimes and has ordered an investigation into the pardons process.

Clashes between demonstrators furious at the pardon and police erupted last week, as mob of thousands protesters attempted to converge on the national parliament in Rabat and stage a sit-in. At least 63 people were injured.

Galvan, whose whereabouts are now unknown, was one of 48 Spaniards serving time in the North African country, who were granted royal pardon on Morocco 'Throne Day' together with more than 1,000 local convicts.

It was initially believed that Galvan was freed on the request of Spain's King Juan Carlos, who during an official visit to Rabat in July, had asked his Moroccan counterpart to free another Spanish convict suffering from health problems and to be magnanimous with all Spaniards serving time in Moroccan jails.

However, according to Moroccan newspaper La Kome, Galvan release was actually pressured for by Spanish secret services, as the convicted paedophile was not a former university professor, as he claimed, but a spy.

Spanish newspaper El Pais said it found no evidence Galvan worked as Oceanic Sciences professor at Murcia University, before relocating to the city of Kenitra, 40km north of Rabat, less than a decade ago.

His lawyer Mohamed Benjedou said Galvan told him he was a former Iraqi army official, who cooperated with western secret services to overthrow late dictator Saddam Hussein.

The Iraqi native was then reportedly enlisted by Spain's secret service agency CNI (Centro Nacional de Inteligencia).

Documents from Morocco's prison administration describe Galvan as a Spaniard of Iraqi origin, El Pais reported.

He is now believed to be in Spain and it is unclear whether he will be brought back to Morocco.