The neighbourhood pond of Tangua in Dinajpur's Khansama upazila has been giving off what villagers think a strong smell of petroleum.

The water has been covered by an oil slick over the last few days, villagers said.

"What's strange is that the substance is flammable," Rafiqul Islam, a local, told The Daily Star.

Curious villagers soaked paper and clothes in the pond water and set those on fire yesterday.

“A couple of weeks ago a woman told me that the water smelled like diesel. But I did not believe her,” Habibur Rahman, owner of the 25-year-old pond, said.

He added that he noticed "nothing unusual" when he had dug it on roughly 12 kathas of land. 

Villagers over the last two days dug holes in the ground and found that the dirt smelt "diesel".

Khansama Upazila Nirbahi Officer Sajebur Rahman visited the area yesterday and collected samples of water and soil. “We will send these to Dhaka for tests."

Mir Abdul Hannan, a mining expert of Maddhyapara Granite Mining Company Ltd (MGMCL) in Parbatipur, said, “This phenomenon needs to be examined by experts.”