Thailand’s constitutional court has banned the country’s prime minister Somchai Wongsawat from politics for five years and dissolved the ruling party.

Barred from office: Thai prime minister Somchai Wongsawat

Judges made the decision after considering a case of voting fraud against the ruling People’s Power Party and its executive members.

Court president Chat Chalavorn said: “The court has decided to dissolve the party to set a political standard and an example.”

“Dishonest political parties undermine Thailand’s democratic system.”

In the hours before the court ruling was made, one protester was killed in a blast at Bangkok’s blockaded Don Muang airport.

The victim died after a grenade was fired from a flyover near the airport, injuring 22 others in the vicinity.

Anti-government demonstrators from the People’s Alliance for Democracy have occupied the domestic airport site since Thursday.

They have been calling for the resignation of Mr Somchai, whom they accuse of being a pawn for his brother-in-law, former premier Thaksin Shinawatra.

Meanwhile, hundreds of red-shirted government supporters surrounded the Constitutional Court in Bangkok, where judges were preparing to rule on the electoral fraud case.

The activists wore headbands and scarves reading “Against Dictatorship” and “Love Thaksin”.

A decision was made to move the hearing to an alternative court, an official said.

Judges were considering whether to disband three parties in the six-party ruling coalition because some of their members were convicted of vote fraud after elections in December 2007.

The court’s ruling may see Mr Somchai barred from office, but may not necessarily lead to a snap election as MPs may simply switch to a new party.