Ukraine's emergency alert app issued a nationwide air raid warning, as well as alerts for a radiological threat, a chemical attack and street fighting in Kyiv on Sunday evening - all of which turned out to false.
A few hours later, Russia said its equivalent app had also issued false alerts, with both countries claiming their systems had been hacked.
It is still unclear who is to blame for the cyber-attacks and whether the two incidents are connected - the BBC's cyber correspondent Joe Tidy explains what we know so far.
Thousands joined largely orderly demonstrations earlier in the day, before violence erupted in Frankfurt, Berlin, Cologne and Hamburg.
More than 320,000 people demonstrated across France against the rising cost of living and poor public services, with clashes between some protesters and police.
Recordings between a control centre and the train drivers appear to show one train was given clearance to move even though another train had stalled on the track.
People have been killed after a Spanish high-speed train collided with another train south of the capital Madrid, making this the country's worst disaster since 2013.
Dozens of people are feared dead after a high-speed train collided with another train south of Madrid.
BBC correspondent Nick Thorpe reports from Belgrade, where there were rapturous celebrations following the victory of the student-led movement.
The BBC's Europe correspondent reports from Paris where mostly peaceful protests turned into unrest after nightfall.
Police in the southern German state of Bavaria have detained a 33-year-old German man following the fire.
Outside of Paris, Marseille saw some of the worst damage, with shop owners reporting more than 600 premises having been looted.
BBC Verify looked at images appearing to show the Pink Panther rioting in France, but they’re actually AI.
Rioting, looting and vandalism has gripped France over the weekend after protests spiralled out of control across the country.
Laurent Nuñez offered his resignation following a weekend of unrest, but President Macron declined it.
Violence broke out across France, with more than half a million people taking to the streets over the weekend.
A historic town hall in the French city of Limoges has been damaged in an apparent arson attack following a day of nationwide protests
The Pope's first event since his lung cancer diagnosis and surgery saw him recite the traditional Angelus prayer from the balcony of the Apostolic Palace.
An historic town hall in the southern French city of Limoges was set ablaze during national protests.
Demonstrations across the country turned violent, with cars and buildings set alight and shops ransacked.
Police in Albania's capital Tirana have fired tear gas and water cannons onto crowds gathered outside the Ministry of Education where students are among those protesting.
The BBC is on the ground at the Place de la République, where protesters and police clash after weeks of students demonstrations.
Sunderland beat Torreense 2-1 in the Europa League in Portugal.
