BOYNTON BEACH — Investigators in Boynton Beach arrested a Jupiter man last week after an undercover sting in which he traded explicit text messages using the adult hookup app Grindr with someone he believed was a teenage boy.

According to the criminal complaint filed by police, Christopher Siegert, 29, told the undercover officer posing as the teen, “I’m just nervous. I’m afraid you’re a cop.”

Siegert told the investigator that he wanted to perform oral sex upon the “boy” and purchase sex toys at an adult store.

The complaint says that Siegert used the name “R/T” during his online chats with the investigator, who, when prompted by Siegert to reveal his age, said, “Younger then u.”

Siegert allegedly told the undercover officer that he would give him login information for a gay adult Website “if you’re old enough.”

The investigators persuaded Siegert to meet them at a Boynton Beach convenience store, where he was arrested and charged with enticement, a federal count that prohibits the use of interstate commerce—in this instance, an online app—to “knowingly persuade, induce, entice, or coerce a minor to engage in illegal sexual activity.” He faces 10 years to life in federal prison.