Officials said the California secretary of state’s office has received several reports in recent days of possibly illegal drop boxes for ballots in three counties.

Secretary of State Alex Padilla’s office said it is coordinating with local officials to investigate the reports of unauthorized boxes in Orange, Los Angeles and Fresno counties, according to the Orange County Register.

“Operating unofficial ballot drop boxes — especially those misrepresented as official drop boxes — is not just misleading to voters, it’s a violation of state law,” Padilla said in a statement.

The boxes have reportedly been sighted in locations such as churches and local political parties’ offices, the Register noted. Ballot drop boxes are under the jurisdiction of county election officials, according to the newspaper, which added that a felony conviction for operating unauthorized boxes can carry a sentence of up to four years.

Freedom’s Way Baptist Church in Castaic, for example, posted on social media that a metal box out front was “approved and brought by the GOP.” Church officials said they did not have access to the ballots, adding that local Republican officials were responsible for collecting them.

The Fresno County Republican Party also posted what it called a list of “secure” ballot collection sites on its website, none of which are official county drop box locations, according to the official county site.

California Republican officials have defended the drop boxes, saying a 2016 law allowing so-called ballot harvesting permits them. State officials said the boxes do not constitute harvesting, which allows voters to designate someone to submit ballots on their behalf. The drop boxes, however, do not involve a designated proxy signing for the ballots, according to state officials.

“What we did was started to look into it, notified the state, and the Secretary of State issued guidance this afternoon that it is illegal and you can’t do that,” Orange County Registrar of Voters Neal Kelley told the Register. “It would be like me installing a mailbox out on the corner — the post office is the one that installs mailboxes.”