The Saddleworth Moor fire that has raged for more than 10 days is now being treated as arson, police confirmed on Wednesday.
Greater Manchester Police said witnesses had reported seeing people lighting a bonfire around 7.30pm on the night the fire was first reported - June 24 - and officers are “currently pursuing this as a possible line of enquiry”.
The fire service was called to a report of a fire near Buckton Vale in Tameside at 8.19pm on June 24 and have been battling the blaze in “extremely challenging weather conditions” ever since.
Chief Superintendent Neil Evans, Territorial Policing Commander for Tameside, said the fire was now being investigated as arson “following information from local witnesses and initial inquiries”.
Evans added: “The scale of this fire is exceptional and we are treating it with the utmost seriousness.
“That said, we are under no illusion that solid evidence as to where the fire started and what was the cause, will not be easy to establish.
“The areas we have been able to look include dusty ash, burnt peat and grass and, because of this, our work with the fire service will be painstaking.”
Interim Chief Fire Officer Dawn Docx said specialist fire investigation officers at Greater Manchester Fire and Rescue Service were working closing with GMP to investigate the arson.
“Investigations are currently ongoing with a multi-agency approach to find the source of the ignition. There is an area of interest that specialist officers are inspecting,” she added.
Although now under control, the fire is continuing to burn despite the best efforts of all those involved, a statement from GMP said.
“Firefighters are working in extremely difficult and challenging circumstances in Tameside and I can’t praise crews enough – they’ve done a fantastic job and are continuing to work hard to put out the multiple fires across the moorlands,” Docx said.
Evans on Wednesday urged anyone with information to contact the police.
He added: “We recognise the incredible support that the emergency services have received and we now hope that the local community can help us further by getting in touch with any information that could help our investigation.
“Were you on the moors last Sunday and did you see anything that could help us understand exactly what happened?
“If you know anything, no matter how small, it could help our investigation, so please get in touch.”
Docx urged members of the public to be “really careful” with barbecues, discarded cigarettes and glass bottles in the countryside as “fires in the moorlands can spread rapidly so it’s important that we take extra care”.
On Tuesday Downing Street announced that military support would be extended for another three days to help fight the fire.
Around 100 troops from the Royal Regiment of Scotland have been involved in the operation and will continue to work alongside fire crews until 5pm Friday.
On Tuesday the Lancashire Fire and Rescue Service reported that arsonists had been seen lighting fires near Bolton.
The suspects were spotted on Sunday when a police helicopter was sent to survey the area.
On Friday police arrested a 22-year-old man from Bolton in connection with a moorland fire at Winter Hill in Lancashire, on suspicion of arson with “intent to endanger life”.
Seven square miles of land between Tameside and Oldham has gone up in flames since the fire broke out, with fires also spreading and joining in Winter Hill and around Scout Road to the south on Saturday.
Anyone with any information is urged to contact police on 0161 856 9353, alternatively call 101 or Crimestoppers anonymously on 0800 555 111.