German officials say they are investigating a cyberattack on government computers, although they declined to comment on media reports blaming the hacking on a Russian group blamed for infiltration efforts in the United States and Europe.

A spokesman for Germany's Interior Ministry on February 28 said the targeted government agencies had taken measures to investigate the hacks and protect data, without providing detailed information.

"The attack was isolated and brought under control within the federal administration," a spokesman said.

German media reported earlier in the day that a Russian hacking group had penetrated the country’s Foreign and Defense ministries' secure computer networks and had stolen data.

The dpa news agency quoted unnamed security sources as saying the hack by APT28 -- also known as Fancy Bear -- was discovered in December and might have lasted for as long as a year.

The U.S. intelligence community has concluded that Fancy Bear acted on behalf of the Russian government when it allegedly interfered with the U.S. presidential election, a charge the Kremlin denies.

Western governments and security experts previously identified ATP28 as the likely source of an attack on the German parliament in 2015. It has also been blamed for hacking into the computer systems of NATO and governments in Eastern Europe.

The Associated Press in December reported that the group targeted more than 200 journalists globally, breaking into the Gmail inboxes of reporters, publishers, and bloggers.

Based on reporting by dpa, Reuters, and AP