ALBANY, N.Y. (AP) — Allegations that an influential New York state senator forcibly kissed a former staffer are "extremely disturbing," the fellow Democrat who leads the party's primary caucus in the chamber said Thursday.

Senate Democratic Leader Andrea Stewart-Cousins, of Yonkers, said in a statement that an "immediate independent investigation" needs to be started into the allegations against Sen. Jeff Klein, of the Bronx.

"Too many women are discouraged from coming forward because they fear not being believed and attacked," Stewart-Cousins said. "We need to confront sexual assault, harassment and inappropriate workplace behavior head-on and make it clear that it is not acceptable."

In a story first reported Wednesday by The Huffington Post, Erica Vladimer said Klein forcibly kissed her outside an Albany bar in the spring of 2015. Vladimer, now 30, was working at the time for the Klein-led Senate Independent Democratic Conference, whose eight members broke away from mainline Democrats to give Republicans control of the chamber.

She said Klein tried to kiss her while the two smoked cigarettes outside the bar while senators and staffers were celebrating the passage of the state budget.

Klein, 57, denied her allegations during a conference call with reporters held just before the story was posted. He said he welcomes an investigation.

"I want to be crystal clear: This alleged incident never happened nor did anything inappropriate happen in any fashion that evening," Klein said during the conference call, which also included fellow Independent Democratic Conference member Sen. Diane Savino. Savino, of Staten Island, was dating Klein at the time. She said she was also at the bar that night and saw nothing unusual happen between Klein and Vladimer.

Democratic Gov. Andrew Cuomo later Wednesday issued a call for an independent investigation into what he called "this disturbing situation."

Klein's only official response Thursday to Stewart-Cousins' comment came from a spokeswoman.

"As Senator Klein already said yesterday, he welcomes any investigation," Candice Giove said in a statement.

Also on Thursday, Alessandra Biaggi, a former Cuomo aide and Hillary Clinton presidential campaign staffer who was considering a run for Klein's seat, announced that she would challenge him in the primary.

"His #timesup. I'm running against him," Alessandra Biaggi posted on Twitter.

Senate Republican Leader John Flanagan, of Long Island, called Klein "a good and decent person who treats others with respect." He added: "While it may be within the scope of other entities, an investigation into this matter is not within the jurisdiction of the Senate."

The controversy has roiled Senate Democrats as lawmakers started work on the 2018 legislative session, one that will feature battles over state spending and policies in the wake of the federal tax overhaul that's expected to adversely impact New York. As leader of the breakaway Senate Democrats, Klein will play a major role in the negotiations over how the state spends its $150 billion budget.

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