The story took a grim turn when the bodies of one of the men, Dean Finocchiaro, 19, of Middletown Twp., was found at a farm in Solebury Township.
Investigators have said more human remains have been found at the property.
The other missing men are identified as Mark Sturgis, 22, of Pennsburg; Tom Meo, 21, of Plumstead; and Jimi Patrick, 19, of Newtown.
The events of this case can be traced back to the day after Independence Day.
Wednesday, July 5
-Last reported sighting of Jimi Patrick.
Friday, July 7
-Thomas Meo's girlfriend receives her last text message from him.
-Mark Sturgis, a good friend and co-worker of Meo, is last seen. Investigators say he told his father he was going to meet Meo.
-A license plate reader on Street Road in Solebury Township captures a pickup truck belonging to 20-year-old Cosmo DiNardo of Bensalem. The location is near a property on Aquetong Road, which is owned by the DiNardo family.
-A few seconds later, a Nissan Maxima owned by Meo is captured by the license plate reader.
-Last known sighting of Dean Finocchiaro.
LINK: Full coverage of the search in Bucks County
Saturday, July 8
-Meo and Sturgis fail to report to work.
-Meo's mother calls police to report him missing.
-A friend says DiNardo tried to sell him a Nissan for $500; investigators allege it is Meo's vehicle.
Sunday, July 9
-Sturgis' vehicle is located in the area of Peddler's Village.
-Meo's Nissan Maxima is found at a property owned by the DiNardo family in the 2800 block of Aquetong Road.
-The location is near the license plate reader that captured Meo and DiNardo's vehicles, and also near Peddler's Village.
-Police say a search of the property revealed the keys and title of the vehicle. Investigators say the title was not signed by Meo, indicating no legal transfer of ownership.
-Diabetic supplies, believed to be Meo's, are also found in the vehicle. Meo would not willingly leave those supplies behind, the family tells investigators.
-DiNardo tells detectives he was driving a silver 2016 Ford pickup on the night of July 7, with the same tag that was picked up by the license plate reader.
-Sturgis' family reports him missing to state police.
Monday, July 10
-Police begin to focus their search on farmland owned by the DiNardo family on Upper Mountain Road near Route 202 in Solebury Twp.
-Cosmo DiNardo is arrested on a weapons offense from February. His bail is set at 10 percent of $1 million.
Tuesday, July 11
-The Bucks County District Attorney Matthew Weintraub calls DiNardo a "person of interest" in the case.
-Weintraub says he believes "foul play" is involved in the disappearances.
-DiNardo is released after posting bail.
Wednesday, July 12
-Weintraub announces that investigators have found 'important' evidence, but does not elaborate.
-DiNardo is arrested again, this time on charges he stole Meo's vehicle.
-Bail for DiNardo is set at $5 million cash. The judge says it's the highest bail she's ever set.
Thursday, July 13
-At a midnight news conference, Weintraub announces that human remains were found.
-Among those remains are those of Dean Finocchiaro.
For the latest updates on this story, check our ongoing article here.
Meanwhile, police continue to ask the public for tips in this case.
Anyone with information is asked to contact FBI investigators at 1-800-CALL-FBI, or go to tips.fbi.gov.
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