Russian hackers have targeted eight US hospitals in a huge cyberattack after Joe Biden confirmed he would send tanks to Ukraine.
Hacking group Killnet, which is affiliated to Russia, has reportedly claimed responsibility for the cyberattack.
The University of Michigan Hospital and Stanford Health Care Center have reported issues with their websites and portal services.
Multiple websites have reported difficulties since Friday.
It is unclear if other hospitals or public services have been impacted by the cyberattacks.
However, healthcare and appointments at the hospitals currently remain unaffected with patients able to view their medical records.
Killnet is a pro-Russia hacker organisation which has attacked government institutions and private companies since Russia's invasion of Ukraine in March 2022.
The group is thought to have formed around the time of Russia's invasion.
President Biden's decision to send 31 M1A2 Abrams tanks to Ukraine on Wednesday has been met with backlash from Russians after President Volodymyr Zelensky's demand for more heavy armour.
The US are already providing 500 armoured vehicles as part of the help to Ukraine in addition to the $26 billion already committed to Kyiv since Russia's invasion nearly a year ago.
Biden originally rejected demands to send more weapons to Ukraine as he believed it would start a possible nuclear war.
He said in March last year: "The idea that we're going to send in offensive equipment and have planes and tanks and trains going in with American pilots and American crews, just understand … that's called World War III, okay?
"Let's get it straight here, guys. We will not fight the third world war in Ukraine."
However, Biden has since u-turned and admitted the tanks “enhance Ukraine’s capacity to defend its territory and achieve its strategic objectives."
The tanks, which require extensive training, won't be delivered to Ukraine for a while as they are "extremely, extremely complex to operate and maintain."
The president said: "Delivering these tanks to the field is going to take time. Time that we’ll see and we’ll use to make sure the Ukrainians are fully prepared.
"That’s what this is about: helping Ukraine defend and protect Ukrainian land. It is not an offensive threat to Russia.”
Since the announcement on Wednesday, Spain confirmed it will be providing Leopard 2 tanks, which are used by countries such as Poland.
Finland and the Netherlands will also be sending the third-generation German-made tanks to Ukraine.
Britain has pledged 14 Challenger II tanks and Canada have pledged four.
France are also considering sending some of their Leclerc battle tanks to Ukraine.
