Estonia on Thursday said it had thwarted a major wave of cyber attacks against public and private institutions, as Russian hackers claimed responsibility.

"Yesterday, Estonia was subject to the most extensive cyber attacks it has faced since 2007," Undersecretary for Digital Transformation Luukas Ilves said on Twitter. 

"Attempted DDoS attacks targeted both public institutions and the private sector," he added. 

"The attacks were ineffective. E-Estonia is up and running. Services were not disrupted."

The head of Estonia’s computer emergency response team, Tonu Tammer, told AFP the attacks notably targeted the websites of the police, the government and a logistics firm but caused very little disturbance.

[ Read: Russian Use of Cyberweapons in Ukraine and the Growing Threat to the West ]

The Russian hacker group Killnet claimed responsibility, saying it acted in retaliation for the Baltic state’s removal of a Soviet-era World War II memorial this week.

The Baltic state had decided to take down the Soviet T-34 tank from a pedestal in Narva -- a border city with a large Russian-speaking minority -- and transfer it to the Estonian War Museum.

The government had accused Russia of using such monuments to stir up tensions.

Estonia and fellow Baltic state Latvia both have large Russian-speaking minorities that are sometimes at odds with the national governments.

There have been concerns that Moscow could seek to exploit these differences in order to destabilise the countries, which are both EU and NATO members.