55 years age gap of a married Indonesian boy and old woman.

Picture of the couple splashed over the internet.

A 16 year old teenage boy has married his 71-year-old lover in a remote village on Indonesia's Sumatra, officials said, after the unconventional couple threatened a double suicide if their match was thwarted.

The romance began when septuagenarian Rohaya Binti Kiagus Muhammad Jakfar ( the woman ) took care of her neighbor Selamet Riyadi ( the boy ),  who was suffering from malaria, the local village chief said.

"Selamet is too young to marry but we married them anyway because he threatened to commit suicide," village chief Cik Ani, told AFP, adding local officials also wanted them to "avoid the sin of adultery".

"Since the boy is an underage, we have decided to carry out the marriage privately," he said.

Riyadi's father died several years ago and the boy was not properly cared for by his mother, who has remarried, Ani said.

Rohaya has been married twice before, both times to divorcees and has at least one child from the marriages, but this time "she got a virgin," Ani added.

The marriage took place Sunday in the remote Karang Endah village in South Sumatra province, but sparked national interest when a video of the couple's wedding vows went viral on social media outlets.

"He said he was madly in love. We love each other," Rohaya told reporters after the wedding.

The video shows the unlikely couple reciting their vows in front of their relatives and friends.

However, the Indonesian Social Affairs Minister Khofifah Indar Parawansa said she regretted the marriage between the 16-year-old teenager and the 71-year-old grandmother.

Khofifah said the Social Ministry did check and found that the couple was not married according to the district’s rules.

“According to my preliminary estimates, they were not married according to the law because if married through the Office of Religious Affairs it would be clearly impossible because the bridegroom is still underage,” Khofifah said.

Under Indonesian law, the legal age for marriage is 19 for a man and 16 for a woman.