President Donald Trump smashed the retweet button on criticisms of former Vice President Joe Biden a staggering fifty-plus times in one hour on Wednesday.

Trump seems to have been mining the replies to pro-Trump pundit Dan Bongino’s tweet after the International Association of Fire Fighters endorsed Biden on Monday.

NONE of the Firemen I know are supporting Joe Biden for President. 👇🏻 https://t.co/4fxN35oevu — Dan Bongino (@dbongino) April 29, 2019

Trump has reportedly been anxious about Biden’s entry into the race for some time, fretting that the former Vice President can appeal to crossover and blue-collar voters that proved critical to Trump’s 2016 victory.