A week after 10-year-olds Jessica Chapman and Holly Wells went missing, police say they are drafting in extra officers to widen the search area.
Officers are hoping to have triggered memories in yesterday's reconstruction of the girls' last known movements.
Best friends Jessica and Holly disappeared last Sunday near a Cambridgeshire sports centre, but a massive police hunt backed by hundreds of local volunteers has yet to yield any hard clues.
A man in his mid 30s, who was arrested on Friday because he failed to co-operate with police making inquiries into the missing friends, was released at 4.00 a.m today. Police said another man -- in his late 40s -- who was also detained for failing to co-operate, remains in custody. Prior to the release, police had been playing down the arrests.
A newspaper publisher has offered an unprecedented one million pound reward for information. Football star David Beckham - the girls were wearing replicas of his jersey when they disappeared - has appealed for their return.
Jessica and Holly spent a half hour on the Internet shortly before they vanished, but police have quashed speculation that they were using chatrooms before they disappeared.
During yesterday's reconstruction, two child actors meandered through the centre of the Cambridgeshire town of Soham, where the missing girls were last seen nearly a week ago.
Police have already released grainy CCTV footage of Jessica and Holly, who were captured on film near a sports centre wearing the red football shirts not long before they vanished.
Police said at least 250 officers, special waterway search teams and hundreds of local volunteers were taking part in the hunt. Surveillance aircraft have also been used.
Express newspapers have offered one million pounds for information. There was an earlier offer of 150,000 pounds from the Sun and the News of the World, part of Rupert Murdoch's News Corp empire.
The parents of another missing schoolgirl - Amanda Dowler, known as "Milly", who vanished more than four months ago - have sent a letter of sympathy to the families of Jessica and Holly.