Ukraine invasion: How the war is being waged online

Russia's invasion of Ukraine, it has been said, would be the first to introduce a new front line - the internet.

And cyber-attacks have been raging on both sides, with warnings things could escalate.

But a digital war is being waged in many other ways too - from questions about whether technology companies should block content to Russia, to online censorship, the spread of disinformation, and Ukraine's internet facing disruption as missiles fall.

The Anonymous hacking collective has declared cyber-war on the Russian government.

Its claims should be treated with scepticism - but it has reportedly hacked state TV channels to show pro-Ukraine content.

There has also been hacking against Ukraine, with denial-of-service attacks hitting government websites and the emergence of what looks like ransomware without the ability to recover data.

This "wiper" malware - "intended to be destructive and designed to render targeted devices inoperable" - had been found in dozens of Ukrainian systems across the government, non-profit and information technology sectors, Microsoft said.

And the Reuters news agency reported Ukrainian officials had alleged a Belarusian cyber-spying operation was targeting personal email accounts belonging to Kyiv's forces.

In the UK, Business Secretary Kwasi Kwarteng will reportedly hold talks with Paula Rosput Reynolds, who chairs the National Grid, amid fears of a wave of state-sponsored Russian attacks.

And the National Cyber Security Centre has called on organisations to bolster their online defences.

Although, its former head Ciaran Martin told the Guardian newspaper cyber had played "remarkably little part" in the conflict so far.

Internet access is likely to be patchy during any conflict, as bombs and missiles damage networks and equipment.

And on Friday, heavy fighting in the city of Kharkiv saw significant disruption, according to NetBlocks, with connectivity to Ukraine's main internet provider, GigaTrans, dropping below 20% of normal levels.

Entrepreneur Elon Musk, always keen to help out in a crisis, responded quickly to calls for his satellite broadband service, Starlink, to be made active in the country - but it remains hard to tell where it is deployed and how much it is helping.

The Starlink networks offered "hope for connectivity in a worst-case scenario", NetBlocks told BBC News, but its terminals were likely to be in short supply.

"There is truly no silver bullet for staying connected in a crisis," NetBlocks added.

Meanwhile, Citizen Lab senior researcher John Scott-Railton tweeted: "If Putin controls the air above Ukraine, users' uplink transmissions become beacons for air strikes."

In the UK, mobile operators, including O2, Vodafone, Three and EE, have made mobile calls to Ukraine free, with no additional roaming charges for those in the country.

Pretty much as soon as Russia invaded, Ukraine's politicians began asking the big technology companies so many rely on for information and entertainment to play an active role in the war.

"We need your support," Deputy Prime Minister and Digital Transformation Minister Mykhailo Fedorov told Apple chief executive Tim Cook.

"In 2022, modern technology is perhaps the best answer to the tanks, multiple-rocket launchers and missiles."

He also asked Meta to ban access to Facebook and Instagram in Russia.

But the company's head of global affairs, Nick Clegg, said this would prevent people there using them to "protest and organise against the war and as a source of independent information".

Mr Cook was also non-committal, saying Apple was supporting humanitarian efforts and remained "deeply concerned" about the conflict.

YouTube, meanwhile, has said it will halt several Russian channels' ability to make money - and limit recommendations to them

Parent company Google, the world's biggest ad seller, added it would not let Russian state media sell adverts using its tools.

And after consulting with regional authorities, it has disabled live traffic and information about how busy places such as shops and restaurants are

Facebook and Google have also restricted access to some state media accounts in Ukraine, at the request of the Ukrainian government, and banned downloads of Russia Today's mobile app.

Facebook has taken down a network run by people in Russia and Ukraine for "inauthentic behaviour", posing as independent news entities and creating fake personas across its channels.

And it warned about a hack called Ghostwriter accessing the Ukrainian military and public figures' social media, via email, to post disinformation.

Additional privacy measures rolled out in Ukraine had been enabled in Russia following reports of the targeting of people protesting about the war, the social network said, including:

There will be debate about how big a role corporations should take in a war but some felt it was a moral imperative.

"It's appropriate for American companies to pick sides in geopolitical conflicts - and this should be an easy call," former chief security officer at Facebook Alex Stamos tweeted:

Russia's government has imposed partial blockades on Facebook and Twitter, after clashes with the companies.

The country's communication regulator, Roskomnadzor, accused Facebook of "violating the rights and freedoms of Russian citizens", after Meta refused to stop fact-checking and labelling content from state-owned news organisations.

And NetBlocks reported Twitter had been heavily throttled across every major Russian telecom provider.

BBC News reporter Steve Rosenberg also said access to Twitter was "being severely restricted".

"This message got through but took a while," he tweeted.