New photos of Weiner surfaced Sunday amid growing demands for his resignation.
The photos, posted on tmz.com, show Weiner photographing himself as he poses in front of a mirror apparently at the House gym.
Some are naked full body shots. In one picture, Weiner is holding his camera and hiding his private parts.
According to TMZ, the pictures were sent online to at least one woman.
Weiner left for a treatment center Saturday, but first he insisted he wants to get back to work on behalf of his constituents.
Around two dozen of those constituents rallied outside one of his district offices Sunday, calling for his resignation.
Weiner supporters were there as well.
"He should not be convicted in the press," one supporter said. "If he violated a law, let him be convicted by a jury."
The No. 2 ranking House democrat joined other top party leaders in urging Weiner to resign.
"It seems to me extraordinarily difficult that he can proceed to represent his constituents in an effective way given the circumstances, this bizarre behavior," Rep. Steny Hoyer said.
Republicans are hoping for an end to the Weiner scandal as well.
"We have to get this behind us because it's a distraction," Rep. Paul Ryan said. "So, yes, he should resign. I don't take any pleasure in saying that."
New York Sen. Charles Schumer is said to have a strong influence on Weiner, but so far he is not calling on him to resign.
"For those of us who are long-time friends of Anthony, this is heart breaking," Schumer said.
Weiner has not said when he'll emerge from the treatment center.
His office indicated Saturday that he'll ask for a "short" leave of absence from Congress to seek professional help.