Two Germans have been sentenced to nine months in prison and three strokes of the cane in Singapore for breaking into a depot and spray-painting graffiti on a commuter train.

Andreas Von Knorre, 22, and Elton Hinz, 21, who had pleaded guilty, expressed remorse while being sentenced on Thursday as rights groups criticised the country's judicial system.

"The Singapore judicial system's shameful recourse to using torture - in the form of caning - to punish crimes that should be misdemeanours is indicative of a blatant disregard for international human rights standards," said Phil Robertson, deputy director of the Asia division of Human Rights Watch.

Von Knorre and Hinz were accused of vandalism and trespass after they broke into one of Singapore's train depots last November to spray-paint a carriage.

The men then fled Singapore, only to be tracked down in neighbouring Malaysia in an international manhunt and then brought back to the city-state to face trial.

'Darkest episode'

Singapore, well known for its cleanliness and its zero tolerance for crime, uses the rattan cane to carry out the sentence.

Prisoners are stripped and strapped to a wooden trestle with a medical officer on hand to intervene if necessary.

People who have been caned have called the pain excruciating.

"This is the darkest episode of my entire life," said Von Knorre while being sentenced. "I want to apologise to the state of Singapore for the stupid act ... I've learned my lesson and will never do it again."

Hinz said: "I promise I will never do it again. I want to apologise to you, and my family for the shame and situation I've put them into."

In recent years, Singapore has poured funds into nurturing and promoting its arts scene, including opening some public space for graffiti, as it works to change its image beyond just an efficient business hub.

But its artists remain hindered by strict censorship and a tight government grip on the media.

In 2012, local artist Samantha Lo was arrested for placing humorous stickers on traffic light poles and spray-painting road signs, triggering an outcry and heated debates on the vandalism laws.

Source: Reuters