Municipal police from Newtown, Middletown, Solebury, Buckingham and Plumstead Townships are involved in the investigation, along with county detectives, state police and the FBI, Weintraub said. The charges do not relate or pertain to this case, Weintraub said.
Their search still centers on a Solebury township farm.
DiNardo, who was arrested on an unrelated gun charge earlier this week, posted bail on Tuesday night.
The missing men's photos have begun to appear on digital billboards along highways in the area.
"We don't pick a person and try to build a case against them", he said, referring to Cosmo DiNardo.
The others missing are 22-year-old Mark Sturgis and 19-year-old Dean Finocchiaro.
Jimi Tar Patrick, 19, of Newtown Township, was the first to go missing last Wednesday.
Authorities said they know more than they're telling.
Weintraub said the next press briefing will likely occur at 11 a.m. Tuesday.
HuffPost's attempts to reach DiNardo's parents and other family members for comment have been unsuccessful. He said DiNardo "may or may not be" a part of the investigation in days to come.
"We're going to continue in the direction that we're going ... we are going to keep digging and searching that property until we are confident they are not there", he said. According to the arrest report, DiNardo suffers from mental illness and had been involuntarily committed to a mental institution at that time.
The family of DiNardo, 20, of Bensalem, owns both Solebury properties that have been searched thus far.
Sturgis and Meo are longtime buddies, while Finocchiaro is a mutual friend. "I can't say if there is that type of information, but if there is, I beg of you to please give it to us and let us run it down".
"We've dedicated a ton of investigative resources there", Weintraub said.
Law enforcement workers walk down a blocked off drive way, Tuesday, July 11, 2017, in Solebury, Pa.as the search resumes for four missing young Pennsylvania men feared to be the victims of foul play.
While the charge was dropped in February, authorities have refiled the charge on Monday.
When asked whether he thought the missing men were alive, the district attorney replied, "I hope and I pray that would be the best outcome". They were reported missing since Wednesday to Friday of last week.
Matthew Weintraub, the Bucks County District Attorney, on Monday called the search an "all hands on deck" situation as local and state police and the Federal Bureau of Investigation look at "all possible leads". Phone calls to Meo's family have not been returned. At a press conference on Monday he said officials have been treating the disappearance of the men as criminal investigation all along. Online records do not say why the charge was initially dismissed.