More than 100 people forced to leave their houses as a blaze spread across heathland in Dorset are returning home.
Up to 170 firefighters tackled the fire at its height as it raged across 200 hectares of land at Canford Heath.
People living nearby gathered at a local school and sports centre as strong winds fanned the flames, a Dorset Fire Service spokesman said.
Dorset Police confirmed on Monday morning that they were treating the fire as arson.
The heathland is an internationally important wildlife habitat
Ben Ansell, of the fire service, described the blaze as a "very serious fire in a very significant bit of urban heathland".
"This piece of heathland, I can't stress, is of European importance so it is very saddening that we've had such a serious fire here tonight," he added.
"We've had firefighters from across Dorset and Hampshire fighting the fire, which I can now confirm is fully under control and we're just damping down."
The fire service received a total of 250 emergency calls alerting them to the blaze on the heath, close to the town of Poole.
A Dorset Police spokesman said homes in several streets in the Canford Heath area were evacuated as a precaution.
I've lived here for 21 years and this is by far the biggest fire in all that time. Highly spectacular against the night sky but lethal as we've heard reports of house roofs catching fire.Chris Bayliss, Poole
I opened the curtains to see an orange sky and a police helicopter overhead. Outside I heard a voice coming from the helicopter megaphone telling people to evacuate their houses and to follow police instructions; on no account was anyone to go closer to the flames or try to tackle them.
I took a walk to get to a better vantage point and saw lines of cars (possibly an exodus from effected areas). Fire engines, police cars and ambulances were whizzing in all directions; blue lights flashing against the orange and black skyline.
Groups of onlookers started to clump together - one with a radio scanner tuned into the emergency services so we could hear what was going on. The power lines (close to the fire) had been switched off for obvious reasons and no lights could be seen, apart from the odd fire vehicle moving along the ridge of the scortched heath. It's all very quiet now and most of the rubber neckers have gone home (me being one of them).
David Kuziara, Canford Heath, Dorset
I think that the emergency services did a fantastic job on scene and in the surrounding area and just feel that this should be brought to attention.
Alex Lewis, Poole, Dorset
The fire brigade and police look as if they have the situation under control now. The only trouble they seem to have had is getting to the fire and stopping it spreading - the heath is a maze of roads and cul-de-sacs, and it's not easy to find your way around if your don't know where you're going.
David Way, United Kingdom
We are at Bournemouth University, and could see the fire from there, several miles away. There was alot of smoke in the air, with a red tint against it. At times flames could be seen above the horizon. We have seen several emergency vehicles go past, including ambulances. Hope no-one is seriously hurt!
I live on Canford Heath. When I heard about the fire at around 8pm I decided to go for a walk as all the roads around me had been closed. To my astonishment the fire was huge and out of control. I walked up to houses where you could see an orange glow in the sky.
At one point I was standing outside peoples' homes and watching the fires lick the trees in their gardens. These people had already been evacuated. The experience was incredibly frightening. We are used to fires in this area, but nothing quite like this.
Rachel Light, Poole