An unidentified, antiseptic type smell left dozens of residents across Burnley and Padiham holding their noses on last night.
Social media was flooded with comments about the odour, which the majority of people said smelt like TCP or Germolene.
Claire Whittaker noticed the smell at around 10pm, outside her home in the Sycamore Avenue area of Burnley, but people in Ightenhill, Padiham and towards Pendle reported sniffing it too.
Claire said: “It was a really strong hospital type smell that was just like TCP.
“It wasn’t very nice at all and it lasted for ages.
"I thought it was me at first but when other people said they could smell it too I knew it was real.”
Burnley Borough Council’s Environmental Health Department did not receive any reports of the smell and a spokesman for Burnley Fire Station said they were not aware of any incidents that could have caused it. The Environment Agency is now looking into the case of the mysterious whiff.
A spokesman said: “We have not received any complaints about the smell but we are aware of it and an officer in the Lancashire area is already looking into it.”
One suggestion for the cause of the whiff was the sewage works or a chemical company disposing of products in the canal.
And there was even a claim that it was caused by paranormal activity as, in many haunting cases, witnesses report smelling unlikely or unusual smells with no obvious source.
Foul or putrid odours, like the one in Burnley, are often reported by witnesses.