A boy suffered injuries from an underground sewer explosion when he tossed a lit firecracker inside.

CCTV footage shows the youngster with his friends walking to a pavement and trying to lift open a manhole cover in Sichuan province, China, on February 8.

He threw the explosive into the hole before there was a blast that sent several covers and dozens of bricks from the pavement flying in the air due to pent-up methane gas that ignited.

After the thick smoke cleared from the scene, it revealed the boy lying on the ground and barely able to move. A man who happened to be walking by ran over to his help and carefully sat him up.

He then lifted him in his arms and carried him away from the site of the explosion, which was now covered in debris.

Other worried passersby also rushed over to the injured boy, who had to be rushed to a hospital with multiple abrasions he had sustained from the accident.

Fortunately, none of his injuries were found to be severe or life-threatening.

Police later cordoned off the area with a warning line to prevent anyone from accidentally falling in.

The Jinbao New Area Management Committee of Pingchang County later said in a statement: 'On the morning of February 8, 2024, at around 11:20 am, three children ignited firecrackers on the sidewalk outside the Waterfront Elegant Residence community in our county's Jinbao New Area, and one of the children threw the firecracker into the sewer manhole, causing the manhole cover to be blown open and resulting in minor abrasions to the child.

'After the accident, the injured child was promptly taken to the County People's Hospital and was found to have no major injuries after examination.'