A Twitter war erupted Thursday between President Donald Trump and Idaho Congressman Raul Labrador.

First, Trump tweeted in the morning, “The Freedom Caucus will hurt the entire Republican agenda if they don’t get on the team, & fast. We must fight them, & Dems, in 2018!”

Labrador, one of the founders of the conservative Freedom Caucus in the House, responded with this tweet: “Freedom Caucus stood with u when others ran. Remember who your real friends are. We’re trying to help u succeed.”

@realDonaldTrump Freedom Caucus stood with u when others ran. Remember who your real friends are. We’re trying to help u succeed. — Raúl R. Labrador (@Raul_Labrador) March 30, 2017

Labrador actively campaigned for Trump in the final weeks of the presidential campaign, when few other members of Congress would. He stumped for Trump in Florida, Arizona and Utah the week before the November election.

The Washington Post reported that Trump “effectively declared war Thursday on the House Freedom Caucus, the powerful group of hard-line conservative Republicans who blocked the health care bill, vowing to ‘fight them’ in the 2018 midterm elections.”

Meanwhile, Politico, in a story headlined “Freedom Caucus reckons with wrath of Trump,” reported that the Freedom Caucus is in “soul searching mode,” and one member, Rep. Ted Poe, R-Texas, quit the caucus on Sunday over its split with Trump on the GOP health care bill. Poe told Politico that the Freedom Caucus’ strategy on the issue “hurt their credibility.” Politico also had this comment from Labrador:

“When you’re right in the middle of the battle, and you’re getting all this pressure from the White House and your leadership and fellow members, it’s difficult to stand your ground because no one likes to not be liked,” Labrador said. “But the reality is that if we all went home next week with a bill with only a 17 percent approval rating, I think we would all regret that vote.”

In the afternoon Trump tweeted again, this time directly criticizing Labrador and two other Freedom Caucus members for not backing the GOP health care bill, writing, “If @RepMarkMeadows, @Jim_Jordan and @Raul_Labrador would get on board we would have both great healthcare and massive tax cuts & reform.”

And Labrador tweeted another response of his own, writing, “@realDonaldTrump R’s promised to repeal ACA’s ‘knot of regulations, taxes, and mandates.’ AHCA fails to to do so and polls @ 17%.”

Labrador told a Boise TV station in a telephone interview on Thursday afternoon, “The problem is that he has been convinced by some people that this bill fully repeals Obamacare and it does not. This bill does not fix the problem.”

The third-term GOP congressman from Idaho’s 1st District told KBOI2 News, “He can’t bully members of Congress. I’ve been doing this for a while, and I respond to my constituents.”