Rep. Eric Swalwell (D., Calif.) mocked Sen. Susan Collins (R., Maine) and her staff in a Thursday morning tweet for talking about receiving threats over the Brett Kavanaugh confirmation fight.

As a moderate Republican, Collins has spoken about getting "ugly voicemails" and "threats" to her office because she is a potential swing vote on Kavanaugh's confirmation to the Supreme Court. She said in an interview that she did not want to minimize the mistreatment of Kavanaugh's accuser, Christine Blasey Ford, but Swalwell still went after her.

"Boo hoo hoo. You’re a senator who police will protect. A sexual assault victim can’t sleep in her home tonight because of threats. Where are you sleeping? She’s on her own while you and your @SenateGOP colleagues try to rush her through a hearing," Swalwell tweeted, linking to a story about the threats directed at Collins.

Boo hoo hoo. You’re a senator who police will protect. A sexual assault victim can’t sleep in her home tonight because of threats. Where are you sleeping? She’s on her own while you and your @SenateGOP colleagues try to rush her through a hearing. https://t.co/bnhtkM9HGy — Rep. Eric Swalwell (@RepSwalwell) September 20, 2018

Swalwell's attack comes after Collins called for ample protection for Ford and her family, noting she was facing a particularly difficult situation.

"I think we need to provide her with any protection that she may ask for, for herself and for her family," Collins said Wednesday on the Maine radio station WVOM. "I would note that Judge Kavanaugh also has received some threats and goodness knows, and I don’t mean to equate myself with either of them, but my office has received some pretty ugly voicemails, threats, terrible things said to my staff and so this has been a very ugly process and I think that is very unfortunate for everybody involved."

As the Senate has worked through Kavanaugh's confirmation process, Collins' office has received abusive phone calls. One caller told Collins to vote against Kavanaugh and not be a "dumb bitch," and another said she couldn’t pretend to be naive about Kavanaugh destroying the "right to choose what women do with their bodies." Audio of the calls show both callers said "f—k you" to Collins.

Swalwell appeared to dismiss the calls and said Collins instead should be worried about Christine Blasey Ford, the woman accusing Kavanaugh of sexual assault when they were both back in high school.

Ford told the Washington Post that Kavanaugh, then a junior in high school, attacked her when they were at a party in Maryland in the early 1980s. She alleged Kavanaugh forced her onto a bed, groped her, and tried to remove her clothes while he was heavily intoxicated, all while his friend Mark Judge watched. She said she managed to escape after Judge jumped on them, sending them tumbling and giving her an opportunity to get out of the room.

Kavanaugh has denied the allegation and released a second statement on Monday where he said he is willing to talk to the Senate Judiciary Committee again. Before Ford's name was released, Judge also denied the allegation.

Since coming forward, Ford's attorney has said her client has received death threats and that her email was hacked. Ford took her family and left their home amid the death threats.

Senate Judiciary Chairman Chuck Grassley (R., Iowa) has postponed the committee vote on Kavanaugh and scheduled a hearing on Monday for Kavanaugh and Ford to testify. An attorney for Ford said her client wants an FBI investigation conducted into the allegations before she agrees to testify.

Democratic Sen. Chris Coons (Del.) didn't address the abusive phone calls his colleague Collins has received and instead said people feel very passionate about Kavanaugh's confirmation. An MSNBC panel echoed a similar defense of the threats and abuse.

Swalwell deleted the tweet and apologized for it.

"Sexual assault victims deserve respect. And senators shouldn’t be threatened by the public. I said something stupid and minimized ugly behavior. That tweet is deleted and I’m sorry for that," Swalwell said.

Sexual assault victims deserve respect. And senators shouldn’t be threatened by the public. I said something stupid and minimized ugly behavior. That tweet is deleted and I’m sorry for that. — Rep. Eric Swalwell (@RepSwalwell) September 20, 2018

UPDATED 10:02 a.m.: This article was updated to include Collins' comments about providing protection for Ford.

UPDATED 11:29 a.m.: This article was updated to include Swalwell's apology.