BISMARCK, N.D. (AP) — North Dakota’s longest-serving state senator is declining to comment on whether he’s the subject of the ongoing investigation following a report that he’d traded scores of text messages with a man jailed on child pornography charges.

Republican Sen. Ray Holmberg had previously announced plans to resign Wednesday, six months before the end of his term.

When asked about the reason for his early departure, he told The Association Press: “There is a time.”

Police and federal agents in Grand Forks seized video discs and other items from the Holmberg’s home in November.