Lithuanian officials say government websites have been hit by cyberattacks for the third time this month.

The latest so-called denial-of-service attacks disrupted the websites of Parliament and the ministries of finance, defense, agriculture and others for about 30 minutes on Thursday.

Police launched an investigation but couldn't immediately say who was behind the Thursday attacks and those earlier this month. The most intense attacks happened on April 11 during a meeting of Crimean Tartars in Lithuania.

Arvydas Zvirblis, head of the Infobalt cybersecurity committee, said "these coordinated attacks are unpredictable and can cause serious damage." He said Lithuania needs to upgrade its cyber defense capabilities.