Russia summoned Italy's ambassador to Moscow on Friday over an Italian television report in a part of the Kursk region captured by Ukrainian troops, the foreign ministry said.
The ambassador faced a "strong protest" due to Italian broadcaster RAI's reporting team which "illegally entered Russia to cover the criminal terrorist attack by Ukrainian soldiers against the Kursk region", the ministry said in a statement.
It warned that the "actions by the Italian citizens fall under Russia's Criminal Code".
The ministry said that "the competent authorities are taking the necessary steps to establish all the circumstances of the crimes committed by the RAI staff to assess the legal position and take corresponding measures".
The Italian television broadcaster's flagship newscast aired an exclusive report Wednesday, showing journalists driving across the border into Russia accompanied by Ukrainian military.
They were shown driving in an armoured vehicle past Russian road signs before arriving in the town of Sudzha, around 10 kilometres (6 miles) from the border, where a journalist talked to locals. Ukraine has claimed full control of Sudzha.