A mother is desperately searching for her 10-year-old son after he was allegedly kidnapped by his anti-vax dad and taken to Panama, with Interpol issuing an international warrant for his arrest.

The mum, who has been named as Melanie Brandauer and who is from Germany, is currently in Panama looking for her son Raphael, 10, who is said to have been kidnapped by his Belgian father, who then took him across the Atlantic Ocean to Central America.

Melanie went to the train station in the German city of Cologne to pick up Raphael after the Christmas holidays, which he had spent with his father. But the young boy never showed up.

The mum could not call her ex or her son because their mobile phones were reportedly switched off.

But she did find a letter from the dad, who has been named in Belgian media only as Koen, that was addressed to her.

She said: “In his letter, he says that it’s too much for him if he also has to let his child be vaccinated, that he can’t take it anymore and that he is taking Raphael with him.”

The mother raised the alarm and investigators quickly determined that the father had taken a flight out of Amsterdam heading to a non-European country.

The family reportedly have clues that lead them to believe that the father and the son are currently in Panama, which is a theory the police have not ruled out.

The distraught mother’s current partner, who has not been named, said: “The father unregistered my stepson from school.” This was reportedly done by fax using a foreign phone number.

The dad is said to have left the country with about 60 kilogrammes (132 lbs) of luggage, and now Interpol have issued an international warrant for his arrest.

The mum has since gone to Panama in a bid to find her son. The father reportedly currently faces a minimum of five years in prison.