Debris fell to earth in Stung Treng province’s Borei O’Svay Sen Chey district near Laos on Thursday following a loud explosion, with more landing across the border.

Authorities have yet to identify the nature of the debris.

Metal and plastic landed across the Cambodia-Laos border on Thursday morning, Stung Treng provincial police chief Mao Dara told The Post.

Police have launched an investigation, but the nature of the debris and how it came to fall from the sky has yet to been concluded, he said.

“Only small pieces of debris landed in Cambodia. More landed on Lao territory than ours. I cannot inform you of the results of the investigation until it is complete,” Dara said.

Prak Savorn, a resident of the area, told The Post on Thursday that before leaving for work, he heard an explosion and saw smoke in the sky. Debris began falling, with some landing in Cambodia and some in Laos. The incident shocked Cambodians and Laotians in the area, he said.

“I heard villagers saying there was an announcement in Laos [on Thursday] that a spacecraft was launching in China. This might be part of the debris from a Chinese spacecraft that fell on five southern provinces in Laos. That was what I overhead Lao people saying,” Savorn said.

Doung Chanty, the head of the 701 border protection police based in O’Svay commune, told The Post on Thursday that debris landed on Borei O’Svay Sen Chey district’s Ou, O’Svay and Preah Romkil communes.

In Laos, debris landed on houses and pagodas, and more landed there than in Cambodia. No one was injured on either side of the border, he said.

“We will investigate the debris that landed on Cambodia, while Laos will look into the debris that fell on their territory. We did not work with them."

“For the debris that landed on Cambodian territory, our specialised team will investigate it. I cannot say anything more. We need to wait for the investigation to conclude,” Chanty said.

The debris was made up of circular pieces of metal and plastic that resembled machine parts, Chanty added.

He said he could not confirm whether the debris came from a spacecraft.

Debris fell on Cambodian soil after an explosion was heard over Preah Vihear temple on December 23, 2016.

Cambodia and Thailand were locked in a conflict over the temple at the time, with Cambodian authorities saying the debris came from a Thai spy plane.