JAKARTA: At least 30 people, including several children, were killed when a fire ripped through a private home that operated as a matchstick factory in Indonesia on Friday, authorities said.

Pictures from the scene showed blackened corpses lying on top of each other in the burnt-out house after the blaze, which authorities said broke out early Friday afternoon.

TV footage showed plumes of black smoke billowing from the home in the town of Binjai in North Sumatra, about 70 kilometres (44 miles) west of provincial capital Medan.

"We don't know what caused the fire but it has been extinguished," the head of North Sumatra's disaster agency Riadil Lubis told AFP, adding that at least three children were among the dead.

"We've sent teams there," he added.

Resident Budi Zulkifli was headed to the local mosque in the Muslim-majority nation when the fire broke out.

"I was about to go out Friday prayers when there was a loud explosion," he told AFP.

"But I don't know what blew up."

Binjai police chief Nugroho Tri Nuryanto said a gas canister explosion may have set off the blaze, but that the cause still needed to be confirmed.

At least three people escaped but most victims may have been unable to flee the scene, he added, while local media said four women escaped.

"They were trapped in a room -- there was no way out," Nuryanto told Tribun News, referring to the dead.

"We're still identifying the victims and scouring the scene."

It was not clear why there were children at the scene. But one survivor, identified only as Pipit, said that they were visiting their parents who worked at the site.

"The children went there at lunchtime," she told Tribun News.

Relatives of the workers have flocked to a local hospital in Medan to identify their loved ones, according to local media.

Deadly fires are not uncommon in Indonesia due to poor safety standards that are routinely flouted, while illegal businesses are also widespread.

This year, dozens were believed to have been killed when an unlicensed gold mine collapsed while, in 2017, at least 46 people were killed and dozens more injured in a blaze that tore through a fireworks factory outside Jakarta.

Seventeen people were killed when a fire ripped through a karaoke bar on Sulawesi island in 2015 and, in 2009, a fire killed 20 people at a karaoke bar in Medan, on Sumatra island. —AFP