Offices of search engine Yandex raided in Ukraine

Ukraine's intelligence agency is searching the offices of Yandex, a Russia-based Internet company best known for its search engine.

Ukrainian authorities earlier this month blocked access to Yandex as well as to several major Russian social media websites. President Petro Poroshenko said the move was made in response to Russia's annexation of the Crimean peninsula and continuing interference in eastern Ukraine.

Most of the Internet and media companies banned by Ukraine, however, are privately owned and have grown over the past decades from start-ups into major international businesses.

Olena Gitlyanska, spokeswoman for Ukrainian intelligence agency SBU, said Monday that Yandex's offices in Kiev and Odessa were searched as part of an investigation on treason charges. It was not immediately clear what the charges were related to.