MINNEAPOLIS (AP) -- A volunteer for Minnesota's Sixth Congressional District DFL committee has resigned after posting a tweet in which he suggested Marines are murderers.

The state DFL Party said Laine Scheuble resigned Friday.

Scheuble had been responding to a tweet by Republican U.S. Rep. Tom Emmer, who congratulated his son for becoming a Marine. Reports say a Twitter user named Laine wrote: "Can't wait to hear about all the Iranian civilians he murdered."

The state DFL Party called Scheuble's tweet "reprehensible."

Scheuble did not return a Twitter message seeking comment.

Days earlier, a state DFL Party staff member referred to a new Navy ship as a "murder boat." Gov. Tim Walz condemned that tweet and Will Davis was removed as deputy communications director but remains as research director.

The Republican Party of Minnesota condemned the posts.