PRAGUE (Reuters) - Russian intelligence services are conducting ‘an information war’ in the Czech Republic, building a network of puppet groups and propaganda agents that could be used to destabilize the country, the BIS counterintelligence service warned on Thursday.

Czech security services have long focused attention on a Russian presence that remains significant a quarter century after the country of 10.6 million broke from Moscow’s orbit and became a member of NATO and the European Union.

In its annual report, the BIS said Russian and Chinese intelligence remained the most active operating in the Czech Republic, and Russia particularly sought to influence Czech media over its role in the Ukrainian and Syrian conflicts.

Russia annexed Crimea from Ukraine in 2014 and Kiev and the West say Moscow is arming and supporting separatist rebels in eastern Ukraine. In Syria, Russia supports President Bashar al-Assad whom Western governments want to see leave power and Russian aircraft have carried out strikes on U.S.-back rebels.

The BIS warned that Russian agents sought to stoke social and political tensions in the country by using puppet groups and supporting populist and extremist groups.

“The infrastructure created for achieving these goals will not disappear with the end of the two conflicts,” BIS said.

“It can be used to destabilize or manipulate Czech society or political environment at any time, if Russia wishes to do so.”

Fears of Russian interference in countries along the European Union’s eastern flank, especially in the Baltics, are growing in the wake of the Ukrainian crisis and NATO has been looking to beef up its defenses.

Additionally a pro-Russian lobby in Czech Republic seeks to boost relations with Russia, while its popular president, Milos Zeman, expresses pro-Russian views.

He has spoken out against EU sanctions on Russia and was the only Western leader to attend the May 2015 celebrations in Moscow to mark the end of WW2, when other Western heads of state stayed away.

Russian intelligence agents, the BIS report said, sought to weaken Czech media through infiltration and by spreading propaganda and disinformation.

The tactics included relativization of truth and objectivity, and promoting the view that all sides lie, the report said.

BIS said “a large number” of Russian intelligence officers were working undercover as part of the Russian embassy in Prague, which is by far the largest foreign mission in the country with around 140 staff, twice as many as the U.S. mission.

In Moscow, there was no immediate comment from the Federal Security Service to the BIS charge, nor was the Russian embassy in Prague immediately available for comment.

Zeman’s spokesman made no immediate comment to emailed questions.