SINGAPORE - The wealthy city-state of Singapore has for the first time lifted the death penalty given to a drug trafficker, commuting his sentence to life in prison and 15 strokes of the cane.

Singapore has hanged hundreds of people - including dozens of foreigners - for narcotics offences in the last two decades, Amnesty International and other groups say.

Yong Vui Kong, a Malaysian who was sentenced to hang in 2009, was spared the gallows on Thursday after a judge ruled he was satisfied that he had acted as a drug courier, rather than having a wider part in the supply or distribution of narcotics.

Singapore has some of the toughest anti-drugs laws in the world, and its customs forms warn arriving travellers of "death for drug traffickers" in no uncertain terms.

Yong's reprieve comes after the squeaky clean state announced changes to its drug rules late last year and allowed judges to impose life sentences and caning on couriers who help the authorities tackle drug trafficking.

In September, Singapore's Attorney General's Chamber issued a statement saying that the Public Prosecutor would testify that Yong had substantively helped the city-state's drugs enforcement agency in "disrupting drug trafficking activities within and outside Singapore".

Yong was arrested in 2007 in Singapore when he was 19 and charged with trafficking 47.27 grams of heroin.

Singapore has also changed its laws on the mandatory death sentence for murder, allowing judges in some cases to impose life imprisonment and caning for some categories of the crime.

So far five murderers on death row have had their sentences changed this year since the law was amended.

However, Deputy Prime Minister Teo Chee Hean told parliament last year that capital punishment was not going away.

"In particular, the mandatory death penalty will continue to apply to all those who manufacture or traffic in drugs - the kingpins, producers, distributors, retailers - and also those who fund, organize or abet these activities," he said.