Ukraine's SBU security service on Tuesday claimed that it had hit the road and rail bridge linking Russia and the Crimean peninsula below the water level with explosives, damaging the pillars underneath.

In a statement, the SBU said it had used 1,100 kilograms (2,420 pounds) of explosives that were detonated early in the morning and damaged underwater pillars of the bridge, which used to be a key supply route for Russian forces in Ukraine in the past.

An official Russian outlet said the operations on the bridge were suspended for about three hours between 4 a.m. and 7 a.m. local time.

It provided no reason for the temporary closure, but said the bridge had been reopened and was functioning as normal.

"Previously, we hit the Crimean Bridge twice, in 2022 and 2023. So today we continued this tradition underwater," the SBU said in its statement.

It also shared video footage that showed an explosion next to one of the many support pillars of the bridge.

New Agency Reuters was able to confirm the location from the structure and bearing elements of the bridge that matched satellite and file imagery of the area. However, it was unable to verify the video.

Russian military bloggers said the attack was unsuccessful and speculated that it had been carried out by a Ukrainian sea drone.

On Sunday, Ukraine launched drones in an operation codenamed "Spider's Web" to attack Russian nuclear-capable long-range bomber planes at distant airfields across Russia.

The 19-km (12-mile) Crimea Bridge over the Kerch Strait is the only direct transport link between Russia and the Crimean peninsula, which Moscow annexed from Ukraine in 2014.

The bridge was a flagship project for Russian President Vladimir Putin.

It consists of a separate roadway and railway, both supported by concrete stilts, which give way to a wider span held by steel arches at the point where ships pass between the Black Sea and the smaller Azov Sea.