KYIV, May 15 - Ukraine’s state security agency SBU raided offices of two Russian state-owned media outlets in the Ukrainian capital Tuesday and leveled treason accusations against a journalist, The Associated Press reported.

Ukraine’s domestic security agency, the SBU, said the raids of the Kyiv offices of the RIA Novosti news agency and RT television were part of its investigation into Russian media outlets being “used as tools in a hybrid war against Ukraine.”

The agency said the head of RIA Novosti’s Ukrainian office, Kirill Vyshinskiy, was detained for alleged treason, a crime that carries a prison term of up to 15 years upon conviction.

Relations between Moscow and Kyiv soured in 2014 when Russia annexed Ukraine’s Crimea and threw its weight behind separatists in eastern Ukraine. The Ukrainian government has long blamed Russian state media for fanning the flames of the war in the east, which so far has killed more than 10,000 people.

Moscow angrily protested Tuesday’s raids. Russian Foreign Minister Sergey Lavrov denounced the Ukrainian action as an “unacceptable” attack on freedom of speech and urged the West to condemn it “without any double standards.”

Harlem Desir, a media freedom representative at the Organization for Security and Cooperation in Europe, a top security and rights group, expressed “serious concern” about the raids.

“The fight against propaganda must not fall short of international standards and should not represent disproportionate interference in media activities,” Desir said in a statement. “OSCE participating states have committed to facilitating the conditions under which journalists from one participating state exercise their profession in another participating state.”

In Washington, U.S. State Department spokeswoman Heather Nauert said the United States shared concern about Russian propaganda, but noted that Ukraine must take care to ensure it abides by the law, including international human rights law.

The raids came several hours before Russian President Vladimir Putin traveled to southern Russia to attend the opening ceremony of a bridge linking Russia and the Crimean peninsula. (ap/ez)