The couple with a 55-year age gap

Rohaya and Selamat Riayadi threatened to harm themselves if they could not marry. Photo / Australscope

A 16-year-old boy and 71-year-old woman have shocked Indonesian society by getting married after threatening to harm themselves if their families blocked the union.

Selamat Riayadi and his elderly bride named only as Rohaya wed in their home village of Karangendah in the western South Sumatra province of Indonesia.

The marriage is not believed to be motivated by financial concerns, as both newlyweds are equally poor.

His family made a dowry payment to hers of 200,000 IDR ($20).

A video of the wedding ceremony shows the young groom put his face in his hands as the union is proclaimed, his expression unreadable.

His new wife sits quietly beside him as the wedding guests go wild with delight.

The wedding venue was the home of a local community leader named as Kuswoyo.

After the video and photos of the wedding spread on Indonesian social media, many questioned whether the union was real.

Selamat Riayadi and Rohaya. Photo / Australscope

But an Indonesian media outlet claims it spoke to Kuswoyo, in whose home the marriage was solemnised, who confirmed the marriage and the couple's threats to harm themselves if they were barred from marrying.

Kuswoyo's permission was needed according to local tradition as Rohaya had been widowed twice.

It was not clear who if anyone gave permission for Selamat to marry.

The official minimum age for boys to marry in Indonesia is 19 but a loophole allows for any marriage within a person's "religious norms".

The Muslim couple have formed a "nikah siri" marriage, recognised by society but not the state, as Islam has no formal minimum marriageable age, only requiring consensus that the would-be bride or groom has reached "maturity".