The source is a former neighbor of Reade's who says that she discussed the heinous accusations with her in the 1990s.
"This happened, and I know it did because I remember talking about it," said Lynda LaCasse.
LaCasse confirmed the graphic details of Reade's account to the Business Insider.
"I remember her saying, here was this person that she was working for and she idolized him," LaCasse said.
"And he kind of put her up against a wall. And he put his hand up her skirt," she added, repeating more details. "She felt like she was assaulted, and she really didn't feel there was anything she could do."
Reade says that Biden assaulted her in a brutal manner in 1993 during the time she worked as a congressional aide at his office. The Biden campaign has denied the allegations.
LaCasse says she told Reade to go to the police at the time.
"I don't remember all the details," LaCasse said. "I remember the skirt. I remember the fingers. I remember she was devastated."
LaCasse says that she's aware there might be repercussions for her coming out publicly about the story. She added that she is a Democrat that still supports Biden.
"I personally am a Democrat, a very strong Democrat," she said. "And I'm for Biden, regardless. But still I have to come out and say this."
Insider confirmed through public records that LaCasse lived next to Reade.
Here's more about the allegations against Biden:
“It Shattered My Life": Former Joe Biden Staffer Tara Reade Says He Sexually Assaulted Her in 1993 www.youtube.com