A man arrested in connection with the abduction of April Jones was known to the five-year-old's family, it has emerged.
The 46-year-old man from the Machynlleth area was caught on foot but his empty car was quickly recovered, said police.
Forensic officers were already examining the vehicle and described it as "a vehicle he had use of which is of interest to the inquiry."
Police are also looking at whether April's abduction is linked to another attempted abduction in the Aberystwyth area around one week ago.
It comes as police confirmed that they were also looking closely at the movements of known registered sex offenders living in the area.
It is also understood that the man being questioned is known to April's family but is not a relation.
That would explain why the five-year-old apparently got into a car with the person who abducted her of her own free will.
Officers said the man was arrested by a police patrol to the north of the mid Wales market town around 3.30pm.
The arrest came in the hour before April's parents Coral and Paul Jones were due to make a public appeal for help at a police press conference in Aberystwyth.
April was last seen by another child getting into the driver's side of a grey van in Machynlleth at about 7pm on Monday night. Police said it appeared that she had got into the van willingly, but they did not know if she was led to the vehicle or went there herself.