In the first instance, Mangione was asked by a receptionist at a hostel in Manhattan's Upper West Side to remove the mask so she could compare his face to the photo on an allegedly fake ID.
The 26-year-old Maryland native checked in there 10 days before the targeted shooting that happened on Wednesday, Dec. 4 outside the Midtown Hilton Hotel.
The next situation in which he was seen without a mask occurred on Monday, Dec. 9, at a McDonald's in Altoona, Pennsylvania, where the Greyhound bus Mangione was traveling on stopped for breakfast at around 9 a.m.
In photos released by Pennsylvania State Police, Mangione can be seen at the McDonald's eating a hash brown with his mask lowered. Another photo shows him there with the mask back on.
According to witnesses, one customer joked that Mangione resembled the person of interest wanted in Thompson's slaying. But instead of laughing, the other customer told a McDonald's employee, who called 911.
"The customer recognized, notified an employee and wanted someone to check it out further," said Lt. Col. George Bivens of the Pennsylvania State Police said at a press conference.
Two officers then responded, including a rookie, Tyler Frye, who's only been on the job for six months.
Frye said at the same press conference that after Mangione removed his mask, he "recognized him immediately."
"We didn't even think twice about it," Frye said. "We knew that was our guy.
"It feels good to get a guy like that off the street, especially starting my career this way."
This continues to be a developing story. Check back to Daily Voice for updates.
Click here to follow Daily Voice Arlington and receive free news updates.