Sen. Angus King (I-ME) on Tuesday compared Russian election meddling to the terror attacks of September 11, 2011, during his remarks at a 9/11 Remembrance event in Lewiston, Maine.

“They used airplanes into towers,” King said of the 19 hijackers who carried out the terror attacks. “Now people can use the click of a computer key in St. Petersburg, Russia to attack,” the lawmaker continued, later adding, “It’s an attack that continues and it’s the same kind of attack today that occurred in 2001.”

King made the controversial remarks while addressing firefighters and 9/11 first responders.

17 years later, we still grieve. This morning, I joined Maine people at fire stations in Auburn and Lewiston to pay tribute to the lives lost on September 11th, as well as the first responders who rushed into action that fateful day. #NeverForget pic.twitter.com/7E9KDeR5IW — Senator Angus King (@SenAngusKing) September 11, 2018

Maine Republican Senate nominee Eric Brakey issued a statement criticizing King, describing the lawmaker’s remarks as “crass” and an “insult” to those impacted by the history-altering attacks.

“I am appalled that Angus King, on today of all days, compared the brutal terrorist attacks of 9/11 and the murder of over 3,000 innocent Americans to Russian computer hackers. The two things are simply incomparable, and reflect the deranged thinking of Angus and his liberal allies,” a statement via Brakey reads. “Sen. King’s crass statements are an insult to the victims, their families and our first responders. King should retract his statement immediately and apologize for his shameful remark.”

This is not the first instance in which King has compared Russian hacking with 9/11. In a February interview with CNN, the senator said Russian election interference was “one of the most serious attacks” on the U.S. since September 11, 2001. “This is a serious threat,” he told New Day host Alisyn Camerota. “It’s one of the most serious attacks on our country since Sept. 11.”

King also warned that Russia, along with other foreign powers, will continue to meddle in America’s electoral process.

“But we’re talking about a major attack on our democracy that’s ongoing, that’s going to continue,” he said. “And this is a place where you need presidential leadership.”