Police have confirmed that they have arrested a 46-year old man as part of their investigation to find missing five-year old April Jones.
ITV News understands the man was arrested walking along the side of the road just outside the youngster's home town of Machynlleth.
Police said they had been "actively looking for him" and have described his arrest as "significant".
ITV News' Geraint Vincent reports:
April Jones was last seen getting into a grey vehicle at around 7pm on Monday night. She had been playing with her friends on their bikes near some garages in the Bryn Y Gog estate in Machynlleth.
Police are treating the incident as a suspected abduction and are concentrating searches in the immediate area, while also re-interviewing witnesses, carrying out house-to-house inquiries and watching CCTV.
They confirmed that witnesses say she climbed into the driver's seat of the vehicle and that there was no struggle.
Mr Bevan said the investigation into the events surrounding her disappearance was in a "delicate and time-consuming process" because the witnesses are all children.
Police described the vehicle as being small at front and large at the back, which could match the description of a small van, Land Rover or a Ford Connect-type vehicle.
The van was described as "grey or light-coloured" but dusky conditions could have meant that colours appeared distorted.
Meanwhile, hundreds of residents gathered at a local leisure centre where search parties were organised.
With each party assigned to an area of the surrounding countryside and will be accompanied by a mountain specialist.
Machynlleth is on the edge of Snowdonia National Park and the landscape is difficult to move through. Search parties will also be hindered by heavy rain.
Celebrities have also been helping to circulate the news and pictures of April:
It's every parents nightmare. My thoughts are with Aprils family xxx
News of April's apparent abduction has come as a shock to the small community of Machenlleth, which has just over 2,000 residents.
The town's mayor Gareth Jones said: "I've lived here all my life and I've never heard of anything like this before."
"Anything we can do, we will do it," he added.
Bryan Whitehouse, a resident of Machenlleth, tweeted that the incident has "destroyed our way of life":
Think I can say this for all my friends here in Machynlleth, we are in shock, this has destroyed our way of life forever #FindApril
And to anyone asking why a 5 year old was out at 7.30, we don't live in the city we live in a country community, this doesn't happen here!
Royal Mail is helping with the search by issuing asking postmen and women to remain vigilant. Local binmen have also been given the day off to help with the rescue effort.
A petrol station in Machynlleth remain open throughout the night to provide fuel for people helping with the search.
Nerys Zjalic, the owner of Reads Garage, told ITV News that volunteers had flocked to the town from as far away as 80 miles.
– Nerys Zjalic, the owner of Reads Garage
We heard about the search through social networking sites and there was a lot of people going past our house.
My friend called to ask if we would open so people can get petrol to help in the search. Locals are out in full force searching for her.
Chris Dudley, who works at the Skinners Arms, said the pub was empty last night with many locals searching the town looking for the little girl:
– Chris Dudley, Skinners Arm pub
All the locals are looking for her in this area - the cemeteries, the golf field, playing field, everywhere you can think of.
Police are still looking. There's no one in [the pub] tonight - everybody is outside looking for her.
Dyfed-Powys Police are asking anyone with information about the incident to call them by dialling 0300 2000 333.