Photo courtesy of Chatham-Kent Fire and Emergency Services.

Emergency crews remain on scene in Wheatley after a hydrogen sulphide detector went off yesterday morning.

It’s the same site where the gas was discovered back in early June, prompting an evacuation and state of emergency.

The provincial Hazmat team was on site yesterday and confirmed the gas is present once again in an Erie Street properly but officials still don’t know the source.

Hydrogen sulphide gas is highly toxic, corrosive and extremely flammable.

Erie St N between Talbot and Elm, and Talbot St E between Erie and Little remain closed with 23 residences and 13 businesses evacuated, displacing 52 people.