Dyfed Powys Police have formally named 46-year-old Mark Bridger as the man arrested yesterday in the missing April Jones investigation.
In a move described by experts as 'unusual', police have also released an image of Mr Bridger and of his Land Rover Discovery with the registration plate L503 MEP.
Five-year-old April went missing from Machynlleth at around 7 o'clock on Monday evening.
Mr Bridger is currently being questioned at a police station in Aberystwyth.
Officers are now appealing to anyone who might have seen Mr Bridger or his vehicle in the past few days.
Police say they are in the process of piecing together his movements, and that of the vehicle, from around 5pm on Monday evening through to 3.30pm yesterday afternoon when he was arrested.
Police confirmed Mr Bridger was arrested on the A487 road north of Dyfi Bridge, walking in the direction of Machynlleth.
He was wearing a camouflage green jacket, black waterproof over-trousers and camouflage trousers beneath those.
Police say the Land Rover Discovery was recovered from a repair garage in the Old Station Road area of Machynlleth on Tuesday afternoon.
Detective Superintendent Reg Bevan told journalists: "We are pursuing a number of lines of enquiry, one of which is Mark Bridger."
Police appeal for people to look at these images and come forward if you have any information that could help find #apriljones
Did you see this vehicle between Monday evening and Tuesday afternoon? Did you know Mark Bridger? Did you see him Tuesday pm? #apriljones
Anyone with information, no matter how minor they think it might be, is urged to call the Child Rescue Alert line on 0300 2000 333.
– Detective Superintendent Reg Bevan, Dyfed Powys Police
Do not assume somebody else has already contacted us with information. Even if you feel yours is trivial, it may be the vital piece that we are missing.
Meanwhile April's mother Coral Jones has made an emotional appeal for information on her missing daughter.
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