A sexual assault allegation against former Vice President Joe Biden has sparked criticism from staffers who worked for the presidential campaign of Vermont Sen. Bernie Sanders.

Tara Reade, a former employee for Biden’s Senate office, claims Biden sexually assaulted her in 1993 and recently unearthed video that appeared to show her mother corroborating that claim on a cable news show.

#BREAKING: HERE is the video from August 11,1993's 'Larry King Live' described by @TheIntercept (and Tara Reade) as allegedly featuring her mother calling in and alluding to Reade's sexual assault claims against @JoeBiden (blog here by @ScottJW) https://t.co/fCgEqBnX7n pic.twitter.com/V5FGHskv56 — Curtis Houck (@CurtisHouck) April 24, 2020

“The video of Tara Reade's late mother calling into Larry King to blow the whistle about about Tara's sexual assault is being met with relative silence from a cadre of progressives right now and I want you all to know that I see you. We all do,” a former Sanders campaign adviser said on Twitter in response to the news of the video.

The video of Tara Reade's late mother calling into Larry King to blow the whistle about about Tara's sexual assault is being met with relative silence from a cadre of progressives right now and I want you all to know that I see you. We all do. — Fred (@WaywardWinifred) April 24, 2020

“Progressives didn't make this happen,” Briahna Joy Gray, Sanders’s former press secretary, said in response to a tweet from Donald Trump Jr. criticizing the handling of uncorroborated allegations against Supreme Court Justice Brett Kavanaugh compared to the allegation against Biden. “Corporate Democrats chose Biden.”

Progressives didn't make this happen.



Corporate Democrats chose Biden. https://t.co/95xVE0TkOt — Briahna Joy Gray (@briebriejoy) April 25, 2020

Biden has yet to explain the allegation, but his surrogates have been forced to answer questions about the subject, including Minnesota Sen. Amy Klobuchar, whom many believe is a top contender to be his running mate.

"All women in these cases have the right to be heard and have their claims thoroughly reviewed,” she told NPR .

"I think it's relevant to talk about anything. And I think any woman who feels that she was assaulted has every right in the world to stand up and make her claims," Sanders said about Reade’s claims.