The response comes less than 24 hours after Politico published a piece detailing accusations that one of Sanders's top advisers had forcibly kissed a subordinate woman in her 20s, and one week after the New York Times reported allegations from almost a dozen former campaign workers who say they were harassed and that their claims went ignored.
The New York Times has also reported on multiple claims of mistreatment against female Sanders campaign aides by senior male officials.
The harassment allegations "speak to unacceptable behaviour that must not be tolerated in any campaign or any workplace", Sanders said. "Then he moved his hands to her head and forcibly kissed her, putting his tongue in her mouth as he held her".
Becker has denied any wrongdoing.
Dozens of women and men who worked on the 2016 campaign signed a letter asking to meet with Sanders and his top aides "to discuss the issue of sexual violence and harassment on the 2016 campaign, for the goal of planning to mitigate the issue in the upcoming presidential cycle".
As detailed in a report from POLITICO published on Wednesday, top Sanders advisor Robert Becker is accused of forcibly kissing the female staffer, who is reportedly in her 20s and has remained anonymous out of fear of retribution from Sanders supporters.
"This can't happen in 2020", the woman said in Politico. "You can't run for president of the United States unless you acknowledge that every campaign demands a safe work environment for every employee and volunteer", she added. Though the allegations against Sanders' campaign are far-reaching, the issue of sexual harassment has been pervasive across the political spectrum and beyond, as brought to light in the wake of the Me Too movement.
The reports of harassment are raising questions about whether Sanders can launch a second presidential campaign.
A former female campaign staffer for Sen.
Sanders is one of several Democrats who have announced or are likely to announce a presidential bid. Sen.
Mr Sanders' Twitter apology comes after he said sorry on CNN last week "to any woman who felt that she was not treated appropriately".
The Vermont independent said on Capitol Hill that the alleged misconduct by male aides "was absolutely unacceptable and certainly not what a progressive campaign or any campaign should be about".
Sanders had apologized before, albeit not in such a comprehensive fashion.
The woman said she informed Sanders's 2016 campaign manager Jeff Weaver of the alleged assault.
More than two dozen women have come forward with allegations against campaign staffers. Sanders had issued an apology and said he wasn't aware of the incidents at the time.
Sanders said his 2018 Senate re-election campaign instituted "some of the strongest sexual harassment policies in the country".
- Radio Signals From A Galaxy Light Years Away Have Been Reported
- FDA halts food inspections during government shutdown
- Ocasio-Cortez passed over for influential House committee
- Tulsi Gabbard: Democrat says she will run for president in 2020
- Toyota recalls 1.7 million vehicles in North America to fix airbags
- Longer US government shutdown will hit economy: Federal Reserve Chief Jerome Powell
- Chelsea boss Sarri happy with Hudson-Odoi for Spurs defeat
- US Bolsters Forces in Region as Syria Withdrawal Begins
- Hardik Pandya, KL Rahul suspended pending inquiry into comments on TV show
- USA air travel concerns surface as gov't shutdown drags on