Detectives investigating the disappearance of five-year-old April Jones have until 5pm today to charge or release Mark Bridger.
The 46-year-old has been arrested on suspicion of April's murder.
Dyfed-Powys Police will hold a press conference this afternoon to discuss the case.
Police announced the 'significant development' during a press conference on Friday.
Mr Bridger - covered by a blue blanket - appeared at Aberystwyth Magistrates Court on Friday afternoon, where police were granted a warrant of further detention.
Officers have again emphasised the need for information regarding the movements of Mr Bridger and his blue Land Rover Discovery between 1830 on Monday evening and 1530 on Tuesday afternoon.
The vehicle's registration number is L503 MEP.
Meanwhile more pictures of April have been released as Dyfed Powys Police reaffirmed their commitment to finding her.
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