The House Ethics Committee announced Tuesday that it had formed a four-member panel to investigate Rep. Ruben Kihuen, D-Nev. over accusations of sexual harassment.

The so-called "Investigative Subcommittee" will be chaired by Rep. Kenny Marchant, R-Texas. Rep. Yvette Clark, D-N.Y., will serve as the ranking member. Rep. Jackie Walorski, R-Ind., and Rep. Brian Higgins, D-N.Y., round out the panel's roster.

Kihuen, who was elected to Congress in 2016, announced last month that he would not seek re-election in the wake of the allegations.

The committee is investigating whether Kihuen "may have engaged in sexual harassment" with a campaign aide and a lobbyist. The aide claimed Kihuen propositioned her for dates and sex despite her repeated rejections during his successful 2016 House campaign.

The lobbyist told the Nevada Independent website that Kihuen touched her thighs and buttocks and made unwanted sexual advances while he was a state senator.

Kihuen has denied the allegations and said he will cooperate with the panel's investigation.

Fox News' Chad Pergram and The Associated Press contributed to this report.