The United States has shut its embassy in Kyiv due to what it called the threat of a significant air attack, a day after Ukraine used US missiles to hit a target inside Russia in what the Kremlin has described as an escalation in the war.
Later, after an air raid siren in the early afternoon jangled nerves in the capital, Ukraine's military spy agency said Russia was trying to sow panic by circulating fake online messages about a massive looming missile and drone attack.
"The enemy, unable to subdue Ukrainians by force, resorts to measures of intimidation and psychological pressure on society. We ask you to be vigilant and steadfast," it said.
A US government source said the embassy closure was "related to ongoing threats of air attacks".
The Italian and Greek embassies said they too had closed their doors while the French embassy remained open but urged its citizens to be cautious.
Ukraine on Tuesday used ATACMS missiles from the US to attack an arms depot inside Russia, making use of on the 1000th day of Russia's full-scale invasion of Ukraine.
Russia has been signalling to the US and its allies for weeks that if they give permission to Ukraine to strike deep into Russian territory with foreign missiles, then .
"Out of an abundance of caution, the embassy will be closed, and embassy employees are being instructed to shelter in place," the US Department of State consular affairs said in a statement on the embassy's website.
"The US embassy recommends US citizens be prepared to immediately shelter in the event an air alert is announced."
The US expects its embassy in Kyiv to return to normal operations on Thursday, state department spokesperson Matthew Miller told reporters on Wednesday.
Russia warns of retaliation against Western nations
Russian foreign intelligence chief Sergei Naryshkin said in an interview that his country would retaliate against NATO countries that facilitate long-range Ukrainian missile strikes against Russian territory.
In the early afternoon, the Ukrainian air force told people to seek shelter because of a missile threat.
Senior officials told people not to ignore the alert.
That came shortly before Ukraine's top military spy agency, GUR, issued a statement warning about a Russian psychological operation it said involved fake messages claiming to have been sent by the agency.
"A message is being spread via messengers and social networks ... about the threat of a 'particularly massive' missile and bomb strike on Ukrainian cities today."
