KIEV, December 25. /TASS/. The so-called Crimean prosecutor’s office, an entity within the Ukrainian Prosecutor General’s Office, has opened a criminal case in relation to the first passenger train from St. Petersburg to Sevastopol crossing the Kerch Strait over the Crimean Bridge and arriving in Crimea on Wednesday, the prosecutor’s office informed on its Telegram channel.

"The prosecutor’s office of the Autonomous Republic of Crimea has opened a criminal case in relation to the illegal crossing of Ukraine’s state border by a passenger train from St. Petersburg to Simferopol (a city in Crimea, a stop on the way to Sevastopol - TASS) over the "Kerch Bridge,"" the message informed.

The prosecutor’s office blasted the launch of Russian railway service over the Crimean Bridge as unlawful. "Such actions of the occupant state are in blatant violation of Ukraine’s state sovereignty and territorial integrity, showing a disregard for common principles and norms of international law," the Ukrainian entity stated.

On Wednesday, the first passenger train from the Russian city of St. Petersburg has arrived in the Crimean city of Sevastopol. The railroad section of the Crimea Bridge, which connects Crimea and the Krasnodar Region, was opened on December 23. Trains will run between St. Petersburg and Sevastopol, and between Moscow and Simferopol on a year-round basis.

On Monday, Russian President Vladimir Putin inaugurated railway service on the bridge across the Kerch Strait. The Ukrainian Foreign Ministry expressed its protest to Russia over this.

After the coup d’etat in Ukraine in February 2014, Crimean and Sevastopol officials held a referendum, in which 96.7% of Crimeans and 95.6% of Sevastopol voters chose to secede from Ukraine and join Russia. Eighty percent of the voting population participated in the referendum. The Russian president signed the reunification deal on March 18, 2014, which the Federation Council (upper house of the Russian parliament) ratified on March 21. Despite the results of the referendum, Kiev, along with various predominantly Western countries, refused to recognize Crimea as a part of Russia.

In 2014, the European Union introduced sanctions against Russia due to the events and Ukraine and Crimea, repeatedly expanding and prolonging them since.