Former Secretary of State Hillary Clinton will endorse presumptive Democrat presidential nominee Joe Biden during a virtual town hall event on Tuesday, according to CNN. The report comes as Biden faces mounting pressure to respond to allegations of sexual assault by Tara Reade, his former Senate staffer.

Clinton, who is being dubbed as Biden’s “special guest” this afternoon, teased her appearance in a tweet with a photo of the then-vice president embracing her as then-President Barack Obama looks on in the Oval Office. The twice-failed White House candidate will talk about the impact of the Chinese coronavirus is having on women during the event.

Hillary Clinton tweets that she will be the surprise guest for @JoeBiden's 3pm town hall. CNN's @merica reports she will endorse the former vice president today. https://t.co/918Duxqbrx — Sarah Mucha CNN (@sarahmucha) April 28, 2020

However, it is unclear whether Clinton will address Reade’s allegations. The longtime Democrat figure’s husband, former President Bill Clinton, has faced multiple allegations of sexual assault and infamously engaged in an affair with then-White House intern, Monica Lewinsky.

In an interview with the AP, Reade detailed a 1993 encounter that she says occurred when she was asked by a supervisor to bring Biden his gym bag, as he was on his way down to the Senate gymnasium. She says Biden pushed her against a wall in the basement of a Capitol Hill office building, groped her, and penetrated her with his fingers.

“He was whispering to me and trying to kiss me at the same time, and he was saying, ‘Do you want to go somewhere else?’” she said. “I remember wanting to say stop, but I don’t know if I said it out loud or if I just thought it. I was kind of frozen up.”

Reade said that she pulled away and Biden looked “shocked and surprised,” and replied, “Come on, man, I heard you liked me.”

Reade, who was a staff assistant in Biden’s office at the time, said she wasn’t aware of any direct witnesses to the encounter.

In a Monday interview with Business Insider, Lynda LaCasse, a former neighbor to Reade, said the two discussed her alleged allegation against Biden between 1995 and 1996.

“I remember her saying, here was this person that she was working for and she idolized him,” LaCasse told the news outlet. “And he kind of put her up against a wall. And he put his hand up her skirt and he put his fingers inside her. She felt like she was assaulted, and she really didn’t feel there was anything she could do.”

“She was crying,” LaCasse continued. “She was upset. And the more she talked about it, the more she started crying. I remember saying that she needed to file a police report.”

“I don’t remember all the details,” she added. “I remember the skirt. I remember the fingers. I remember she was devastated.”

LaCasse, a Biden supporter, is the first person to corroborate Reade’s claims.

Further, Lorraine Sanchez, a former legislative staffer to California State Senator Jack O’Connell, told Business Insider that Reade complained about being “sexually harassed by her former boss while she was in DC.”

“What I do remember,” Sanchez explained “is reassuring her that nothing like that would ever happen to her here in our office, that she was in a safe place, free from any sexual harassment.”

Sanchez said Reade was talking about Biden.

Kate Bedingfield, Biden’s deputy campaign manager, issued a statement earlier this month denying Reade’s allegations.

“Vice President Biden has dedicated his public life to changing the culture and the laws around violence against women. He authored and fought for the passage and reauthorization of the landmark Violence Against Women Act. He firmly believes that women have a right to be heard — and heard respectfully. Such claims should also be diligently reviewed by an independent press. What is clear about this claim: it is untrue. This absolutely did not happen,” said Bedingfield.

Biden has not responded to the allegation.

The AP contributed to this report.