A 20-year-old man has been arrested on suspicion of arson with intent to endanger life in relation to a moorland blaze.
Lancashire Police said the man, from Wigan, was arrested on Friday morning by police investigating the fire on Winter Hill, near Bolton.
A force spokesman said the investigation is continuing.
The arrest comes as fire crews from Greater Manchester were released from tackling the blaze at good progress was made.
Greater Manchester Mayor Andy Burnham, who visited crews on the scene on Friday morning, said: "I wanted to come here again today to say a huge thank you to all the crews fighting this fire, including crews from Greater Manchester, Lancashire and many other fire and rescue services.
"They are working incredibly hard and the public are so grateful for their efforts.
"Following assessments of the incident ground on the Greater Manchester side of the hill yesterday, and in consultation with LFRS, today we are able to scale back some of GMFRS's resources from that area.
"Good progress is being made and over the weekend there will be five GMFRS appliances supporting Lancashire."
Fire chiefs declared a major incident last Saturday after two large-scale blazes either side of Winter Hill merged because of increased wind speed.
A 22-year-old man was arrested last week on suspicion of starting one of the fires and later released under investigation.