Hacker group Anonymous claimed responsibility on Monday for disrupting the work of websites of pro-Kremlin Russian media in protest of the invasion of Ukraine. 

The group targeted the websites of state news agencies TASS and RIA Novosti, as well as taking over websites of newspapers Kommersant and Izvestiya and Forbes Russia magazine.

It posted messages appealing to Russians to try to stop the war and not participate as fighters.

"In a few years we'll live like in North Korea. What's in it for us? For Putin to make the history books? It isn't our war, let's end it!", said a message in Russian posted on Forbes Russia's site.

"This message will be deleted and some of us will be sacked and even jailed. But we can't stand this any longer," said the writer, signing off as "concerned journalists of Russia".

The latest cyberattacks come after Thursday's hacking of RT state-funded television channel.

They also follow the downing over the weekend of the websites of the Kremlin, the defence ministry and the Duma lower house of parliament, claimed by Anonymous on Twitter.

The sites have faced a barrage of denial-of-service (DDOS) attacks.

Web monitoring group NetBlocks said in a report on Saturday that Russians were experiencing delays in accessing the websites of the main phone and mobile phone operators, Rostelecom, MTS, Beeline and Megafon.

Ukraine's Minister of Digital Transformation, Mykhailo Fedorov, said Saturday that the country needed IT recruits.  

"We are creating an IT army. We need digital talents. All operational tasks will be given here," he tweeted.