A mystery early morning blast which was heard by people across South Yorkshire this morning was reportedly also heard 30 miles away.
The "massive bang" was supposedly heard in the Rotherham and Meadowhall area at around 5.15am - but there have been no reports of fires or explosions in the area.
Early morning "massive bang" reported at Meadowhall
Twitter user Katrina Smith took to social media to tweet: "Any ideas what the massive bang was at 5.15am today? Rotherham/Meadowhall area."
Now others have come forward to say they also heard the blast - with one saying it was reportedly heard in Saddleworth between Sheffield and Manchester, more than 30 miles away.
Julie Turner wrote on Facebook: "The noises this morning were heard over in Saddleworth apparently."
Tammy Louise Young added: "I heard something while I was stood at bustop at 5am" and Graham Simpson posted: "I heard this at 5:05am this morning as I was getting ready for work."
Others had theories for the reason behind the noise with Jay S Twigg writing: "Be from one of the steelworks always lands up being the steelworks."
Judy Pickorer added: "Fireworks may be if there is not sign or fire or damage" and Simon Greaves wrote: "I've heard this noise a couple times around Woolley Wood bottom."
It is not the first time South Yorkshire residents have been left puzzled by mysterious explosions.
Last October, residents in Long Sandall, Doncaster were left baffled by a massive late night noise with no obvious signs of what had caused the explosion or evidence of damage.
Andrew Hill said: “I felt the whole house shake and windows were rattling. “I went outside and could see smoke near the rail crossing but there were no obvious signs of what had happened.
And in November 2014, several loud 'mystery bangs' that shook windows baffled people across the country.
Dozens of Twitter users from London to Glasgow claimed to have heard the strange noises, which sounded like fireworks or loud aircraft.