German security officials say a cyberattack believed to be directed by Russia targeted journalists and lawmakers in recent weeks.

The domestic intelligence agency BfV says the German Parliament, at least two political parties and an unidentified media company were targeted in a sophisticated email phishing attempt between Aug. 15 and Sept. 15.

A warning bulletin provided Friday to The Associated Press says the attacker used a fake email address purportedly belonging to an individual at the NATO military alliance, of which Germany is a member.

The BfV said its cyberdefense unit determined that clicking an attachment in the email could result in the installation of malicious software.

It attributed the attack to the hacking group APT28, noting "there are indications this campaign is directed by Russian government entities."