Pictured: The last photo of Abigail Williams alive - search scaled back after bodies found

A haunting photo of 13-year-old Abigail Williams walking on railway tracks, taken by her friend Liberty German, may prove to be the last image taken of the girl alive.

Hours after the Snapchat image uploaded to 13-year-old Liberty's account on Monday afternoon, the girls were reported missing to local authorities in their home town of Delphi, Indiana.

The following day investigators announced that they had found two bodies during their search for the missing girls.

Liberty German posted haunting photos from the bridge where they were walking before the teens went missing. Photo: Snapchat

Police have not formally identified the bodies as Abigail Williams and Liberty German as yet, and have not commented on injuries or trauma to the bodies, local news outlet Fox 59 has reported.

But officers said they suspected foul play in the girls' disappearance and the bodies were found less than a kilometre from where they were dropped off to go on a hike.

Liberty German went missing earlier this week in Indiana. Photo: Facebook.

Authorities have not officially called off the search for the girls, but it has now been scaled back, Fox 59 has reported.

"We are investigating this as a crime scene," Indiana State Police Sergeant Kim Riley said at a news conference shortly after the bodies were found on Tuesday.

"We suspect foul play."

Abigail Williams and Liberty German went missing after being dropped off to go for a hike near a local landmark on Monday. Photos: Facebook

People have also started posting their condolences to the family on Abigail mother's Facebook page.

The girls were dropped off at local landmark Monon High Bridge about 1pm on Monday (local time) and were supposed to be picked up from the same spot later.

The two 13-year-olds were supposed to be picked up later on Monday, but were not there when someone arrived to get them. Photo: Facebook

But they were not at the location when someone came to pick them up and they were reported missing by their families at 5.30pm on Monday.

Their families and the wider community launched a large-scale search for the girls.

Abigail Williams disappeared after being dropped off for a walk with her friend on Monday. Photo: Facebook

"The family asked us to thank the communities around Delphi and the people here in Delphi for assisting in attempting to locate the two young children who were missing here earlier,” Sergeant Riley said at the press conference, RTV 6 has reported.

Officers did not comment on whether there were any persons of interest in the investigation at this point.

Liberty's photo of Abigail, posted at 2pm on Monday is the last documentation of the girls.

Liberty German posted a haunting photo of her friend walking on railway tracks before the pair went missing. Photo: Facebook

Their phones had since gone dead or been powered off, authorities said.

The bridge where the girls were walking spans Deer Creek, which is completely abandoned and has no guard rails, according to local media outlet the Lafayette Journal and Courier.

It is listed as one of Indiana Landmark's 10 most endangered historical sites, their website reports.

Abigail with her mother Anna Williams, who has received numerous condolensce messages on her Facebook account since the bodies were discovered. Photo: Facebook
Local police held a press conference after the bodies were found in the search for the two 13-year-olds.

Before the discovery of the bodies, Liberty's grandfather Mike Patty told local media WLFI that he was distraught and worried.

"Missing, abducted, we don’t know for sure,” Mr Patty said.

"The cellphone has been pinging around town – and here there is a cellphone tower – but the ping was last noted around five to six hours ago.

"And they say the phone is now dead."