June 3 (UPI) — Ukraine said Tuesday it successfully carried out a military strike on the Crimean Bridge, the culmination of an operation that took several months to execute.

The Security Service of Ukraine, or SBU, posted to Telegram that it struck the bridge, which connects Russia and Crimea, in an underwater attack.

The aquatic assault, the third strike on the bridge by Ukraine, involved SBU agents who mined the bridge’s pillars over a period of several months. The first explosive device was detonated early Tuesday morning, and SBU officials claim no civilians were harmed in the attack.

The SBU said the structure’s submerged support system was “severely damaged at the bottom level,” with the equivalent of over 2400 pounds of TNT used, which ostensibly left the bridge is in disrepair.

SBU Lieutenant General Vasyl Maliuk, who was in charge of the operation, said via the Telegram report that “the Crimean Bridge is an absolutely legitimate target, especially given that the enemy used it as a logistical artery to provide its troops.”

Ukraine also suffered a major attack Tuesday as its president Volodymyr Zelensky posted to social media around an hour after the assault on the Kerch Bridge happened. He posted videos that purportedly showed bodies on the ground of the northeastern city of Sumy and confirmed that three people were killed and many were injured. “The Russians launched a savage strike on Sumy, directly targeting the city and its ordinary streets with rocket artillery. It was a fully deliberate attack on civilians.” said Zelensky.

He did not mention the Kerch Bridge attack in his post.