There has been a surge in the number of public canings for moral offences in the Indonesian province of Aceh.

Key points: No official tally of those caned for breaching sharia law, but Amnesty counted 108 last year

No official tally of those caned for breaching sharia law, but Amnesty counted 108 last year Canings given for offences such as selling alcohol, gambling, sex outside marriage

Canings given for offences such as selling alcohol, gambling, sex outside marriage Amnesty International is concerned a new code expands use of caning

Amnesty International said more than 108 people were caned in public last year for offences such as selling alcohol, gambling, and sex outside marriage.

The human rights group said this was a substantial increase from previous years, although there is no official tally of those caned for breaching the province's sharia law.

The ABC travelled to the town of Jantho in Aceh to attend a public caning and witnessed the corporal punishment of six gamblers, as well as that of an 18-year-old woman who was convicted of being alone in her own room with her boyfriend.

This is classed as "adultery" in Aceh and is illegal under sharia law.

Kiranti, 18, was convicted of being alone in her own room with her boyfriend. ( ABC News: Adam Harvey )

The young woman, Kiranti, was forced to kneel on a stage in front of a large crowd to receive nine strokes of the cane from a hooded man known as Algojo — the "executioner".

Kiranti was struck on her clothed back with a long cane, wincing with each stroke. After the caning she staggered as she was helped to her feet.

Her boyfriend escaped caning because he was just 16 years old.

"This was not done to humiliate someone," Rahma Daniati, the head of the sharia police in Aceh Besar, told the ABC.

"It is to achieve the deterrent effect, so other teenagers will not follow."

'The violators should be punished'

The province was given autonomy to adopt strict Islamic sharia law after the devastating 2004 tsunami, and is the only part of Indonesia that enforces sharia law.

A new penal code introduced last year extends the use of caning for moral offences and for the first time allows the caning of non-Muslims.

In theory, even an unmarried couple visiting Aceh on holidays could be punished for being alone together.

The sharia enforcer who delivers corporal punishment in Jantho, Aceh. ( ABC News: Adam Harvey )

Ms Rahma said that canings discouraged violations of sharia law.

"First we had a socialisation phase, then an education phase, and this is now the implementation of the punishment phase. The violators should be punished," she said.

Amnesty International's Papang Hidayat said canings were becoming more common.

"If you go back just a few years there were less than 40 canings," he said.

"We are concerned that the new code expands the use of caning as punishment."

'The pain was not so much but I felt humiliated'

In April, an unmarried couple were given 100 strokes of the cane for being alone together, and a Christian woman was caned 28 times for selling alcohol.

Rajuddin, who is 52 years old, was caned last month for playing cards. ( ABC News: Adam Harvey )

A 52-year-old Aceh man, Rajuddin, was caned last month for gambling. He was caught playing cards with a group of friends.

"It was raining so I couldn't go home and I waited at the cafe for it to stop. We all started playing cards to fill up time. And about 12:30 they came and arrested us," he told the ABC.

Rajuddin was jailed and then caned.

"The pain was not so much but I felt humiliated," he said.

"We were just playing for fun but the punishment seemed to be too much while bigger crimes seem to be ignored.

"And we, the little people, the lowest class of society — we seem to always be the ones who get punished."

Human Rights Watch and Amnesty International said corporal punishment breached international treaties against torture and cruel and degrading punishment.

"All are caned in front of a large crowd, usually in front of a mosque after Friday praying. We can't comment on how painful it is, but in our view it is a degrading or inhuman form of punishment," the group said.