BOGOTA, Jan. 23 (Xinhua) -- At least seven people were killed and more than eight others injured in an explosion in a rural area of Tumaco in Colombia's southern department of Narino, local authorities said Friday.

Police said the explosion occurred late Thursday in a village in Llorente district, about 25 km from Tumaco's urban center.

Narino Governor Luis Alfonso Escobar said the cause of the blast remains under investigation and stressed that the incident was not related to armed conflict.

Local media reported that the blast was likely caused by a gas cylinder inside a house.