DELPHI, Ind. -- "Today is the day."
That's the common phrase for investigators working on finding out who killed Delphi teenagers Abigail Williams and Liberty German last month.
Indiana State Police Sgt. John Perrine said on Thursday they are remaining positive despite the fact that one month has gone by without an arrest for anybody in connection with the deaths.
"Not 'Today might be the day,'" he said. "Today is the day. They're optimistic. I've never seen a coordinated effort the way I've seen right now."
There are more than 25 police agencies and hundreds of officers involved in the search.
"We are very optimistic that we are going to find a resolve(sic) to this case," Perrine said.
Libby's grandfather, Mike Patty, addressed the public for the first time since the girls' murders on Thursday.
Patty urged everyone to take just "one minute" to review the evidence that has been released. He said every tip is important and each one will be considered by investigators.
"They don't just go into a bucket," said Patty. "We are confident that together we can bring justice to those responsible for this horrible crime."
The families of both girls recently toured the investigation headquarters in Delphi.
While there, Abigail's grandparents made a stop at a board where the community can leave messages for investigators. Their message to police offered prayers and thanks:
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