State lawmakers want to know where vaccine protesters are getting their money.

Last month, thousands of people showed up in Hartford to fight a plan to end religious exemptions.

On Thursday, Democrats called for a state ethics investigation into three anti-vaccination groups.

They say the groups are lobbyists who need to disclose who's paying for their efforts.

"We've seen Facebook posts where folks have said, 'Bring people who are homeless. Put them in a car and put a sticker on them in a T-shirt, and pay them for the day," said state Sen. Bob Duff.

One group said, "The Connecticut Freedom Alliance is appalled at the outright lies being spread by Senators Looney, Duff, and Abrams."

The Alliance insists it's "a legitimate grassroots organization comprised of parents who are fighting for their children." However, the group did not disclose its specific funding sources.