The U.S. Citizenship and Immigration Services — which processes U.S. citizenship applications — incorrectly told hundreds of new U.S. citizens in Massachusetts this week that they can't vote in this year’s general election because the state’s registration deadline had passed before they took their citizenship oaths, GBH News has learned.

In a statement provided Tuesday night after inquiries by GBH News, USCIS Boston District Director Denis C. Riordan confirmed that some USCIS officials presiding over naturalization ceremonies Monday and Tuesday had informed newly sworn-in citizens that Massachusetts’ Oct. 24 voter registration deadline had already passed, so they would not be able to vote. The agency has since confirmed that in Massachusetts, residents naturalized after that deadline may still register to vote up until 4 p.m. on Nov. 2.

Riordan said the officers based their misinformation on a web page maintained by the Massachusetts Secretary of State, which does not mention the exception.

The agency is reaching out by phone to some 409 new citizens who received the incomplete information during 36 naturalization ceremonies Monday and Tuesday, Riordan said.

GBH News inquired about the ceremonies after being alerted to the erroneous information by Erika Constantine, a Canadian-born resident of North Attleboro who moved to Massachusetts nearly two decades ago and was among hundreds of new citizens naturalized Tuesday.

At her ceremony, Constantine says, the presiding USCIS officer told the new citizens they would not be able to vote in the November general election.

“So I raised my hand and said, ‘That’s incorrect!’” Constantine told GBH News.

A spokesperson for Massachusetts Secretary of the Commonwealth William Galvin confirms that Constantine was right. Newly naturalized citizens may register as late as Monday by presenting their local elections officials with documentation of their citizenship and date of naturalization, and standard proof of residence and general eligibility to vote.

Prior to her Tuesday naturalization ceremony, Constantine had already called the Secretary of the Commonwealth herself to verify the exception for new citizens.

Constantine says she began raising alarms not only at her oath ceremony, but immediately after, worried that other groups of new citizens were being misinformed about their right to vote.

“If I hadn’t said anything, those 20 people [might] not have voted or wouldn’t know they had a right to vote. And that’s just one ceremony,” Constantine said.

“Every single vote matters. … Government officials need to do their duty to inform people correctly,” she said.

Constanine said becoming an American citizen had not been a top priorty for her until the 2020 general election came into focus.

“I have three kids who are U.S. citizens. And I thought it was really my duty, in order to protect them, that I have the ability to vote,” she said.