Rep. Ted Lieu (D-CA) on Saturday accused Gov. Ralph Northam (D-VA) of lying after the embattled Virginia Democrat claimed a racist photo was erroneously published on his yearbook page and reiterated his call for the governor to resign.

Northam said at a news conference he had prematurely apologized for appearing in what he called a “horrific” picture of a person in blackface and another wearing a Ku Klux Klan outfit. The photo appeared on Northam’s profile page in his 1984 medical school yearbook.

“That is not my picture. That is not my person in that picture,” Northam told reporters at the Executive Mansion in Richmond.

While he acknowledged apologizing on Friday, Northam said he had no actual recollection of wearing such racist garb. He spoke to classmates from medical school who agreed. He said he was in the process of obtaining a yearbook so that he could try to determine how the photo even got on his profile page.

“Dear Ralph Northam: You now appear to be lying about a mix-up,” Lieu tweeted, tagging Northam’s official user handle. “You wrote a caption under the racist photograph. It references your interest in being a doctor, and beer, which is in the photo. You knew exactly what you were doing with that photo.

“You need to resign,” he added.

Before he spoke, the Virginia Democratic Party issued a statement demanding Northam’s immediate resignation. The Virginia Legislative Black Caucus, the state House Democratic Caucus, and the state Senate Democratic Caucus all called on Northam to resign late Friday, along with several key progressive groups that have been some of the governor’s closest political allies.

The yearbook images were first published Friday afternoon by the conservative news outlet Big League Politics. The Virginian-Pilot later obtained a copy from Eastern Virginia Medical School, which Northam attended. The photo shows two people looking at the camera — one in blackface wearing a hat, bow tie, and plaid pants; the other in full Ku Klux Klan regalia.

In his first apology on Friday, Northam called the costume he wore “clearly racist and offensive,” but he didn’t say which one he had worn.

He later issued a video statement saying he was “deeply sorry” but still committed to serving the “remainder of my term.”

Nearly every major declared and potential Democratic candidate called for Northam’s resignation after disclosure of the photo.

Northam’s departure would mean current Lt. Gov. Justin Fairfax, a Democrat who is only the second African-American to win statewide office in Virginia, would be the next governor. Northam’s term was set to end in 2022.

Sen. Kamala Harris (D-CA) and former Housing and Urban Development Secretary Julian Castro were the first declared candidates to call for Northam to step down. Among the party’s most prominent Latino figures, Castro called the photo “racist and unconscionable.” Harris wrote on Twitter that “the stain of racism should have no place in the halls of government.”

Sen. Elizabeth Warren (D-MA), who has faced her own troubles over her claims of Native American heritage, followed suit.

On Saturday morning, protesters gathered outside of the Virginia Governor’s Mansion demanding Northam leave his post. RVA Dirt, a self-described “grassroots” political group, reportedly put on the protest. Demonstrators arrived at 9:00 a.m. Eastern Time with signs that read “Get Wrecked Ralph” and “Evict Northam.”

A group of protesters yelling “Hey hey, ho ho, @RalphNortham has got to go!” outside the Governor’s mansion in Richmond —> pic.twitter.com/iFollltBam — Frank Thorp V (@frankthorp) February 2, 2019

I spoke to Jewel Gatling, 39, who’s from Portsmouth but was a speaker at the protest. Says she was just at an advocacy day for MLK day here in Richmond with Gov. Northam. She didn’t believe the yearbook photo was real at first, thought it had been photoshopped. Pictured right. pic.twitter.com/7C2PNlTeYv — Gordon Rago (@gragonews) February 2, 2019

"We're here today because the history of Jim Crow is obviously still alive and living up in the governor's mansion," says local activist Arthur Burton. @GovernorVA #RalphNortham pic.twitter.com/BGmoAlBuVN — Style Weekly (@StyleWeekly) February 2, 2019

Group of protesters gathering in front of the governor’s mansion. pic.twitter.com/40FSzdYPIc — Marie Albiges (@MarieAlbiges) February 2, 2019

Associated Press contributed to this report.