A Singaporean court sentenced a Swiss man to five months' jail and three strokes of a cane yesterday for breaking into a metro depot and spray-painting a train, a punishment that could scar him for life.

Oliver Fricker, a 32-year-old expatriate winding up a posting in Singapore as a software consultant, had pleaded guilty to trespass and vandalism, which are considered serious offences in the city-state.

Mr Fricker was sent immediately to jail but his lawyer Derek Kang said he intended to appeal the sentence, which comprises consecutive terms of three months for vandalism and two months for trespass.

"Obviously he thinks it's too high," Mr Kang told journalists, adding that Mr Fricker would make "full restitution" to the metro operator for the damage he caused. A minimum three strokes of the cane is mandatory for vandalism, according to the written judgment.

The punishment entails being struck with a wooden stick on the back of the thigh below the buttocks, which can split the skin and leave lasting scars.

An Amnesty International researcher described caning as "barbaric" but Singaporean officials were indignant at the intrusion into the MRT subway system, which is classified as a potential terrorist target.

Judge See Kee Oon said in a written ruling that "the incident has reinforced the need for vigilance and adequate security measures," particularly in locations declared protected areas.

Mr Fricker, who was arrested on May 25, eight days after the incident and two days before he was to leave for a new job in Switzerland, showed no emotion as he was led from the courtroom by policemen.

Lance Lattig, a London-based researcher with Amnesty International, said: "Caning is tantamount to torture.

"Singapore presents itself as a modern society, yet at the same time it is using this barbaric punishment which is completely contrary to standards held around the world."