ST. PAUL, Minn. (AP) — A Minnesota state senator who was caught in a sting operation resigned under fire Thursday after he was charged with soliciting a minor for prostitution.

Republican Justin Eichorn, of Grand Rapids, submitted his resignation in a letter to Gov. Tim Walz, Senate Minority Leader Mark Johnson said in a statement.

“This is the right thing to do for his family and the Senate,” Johnson said. “We are ready to move on and do the important work that needs to be done at the Capitol.”

Eichorn, 40, has been jailed since his arrest Monday in Bloomington in an undercover operation targeting commercial sex involving juveniles. He is scheduled to make his first court appearance Thursday afternoon. Court records do not list an attorney who can speak on his behalf.

Investigators had placed multiple ads online offering sex for money, according to the charging documents. Eichorn exchanged text messages with an undercover officer purporting to be a 17-year-old girl for several days until they arranged a meet-up, where he was arrested.

“I saw your post and (sic) chance you are still available tonight?” one asked, according to an FBI affidavit, while a later message asked, “What’s a guy gota do to get with the hottest girl online tonight.”

After his arrest, officers seized two cellphones, a condom and $129 in cash.

The federal charge is attempted coercion and enticement of a minor to engage in prostitution. Six other suspects were arrested in the sting, prosecutors said.

According to Eichorn’s Senate profile, he is married with four children. He lists his profession as entrepreneur and was first elected in 2016.

This is a developing story. Please check back for updates.