- 3 updates
Leeds Civic Hall will be lit up red white and blue tonight and all weekend in memory of the victims of the Nice attack.
84 people have been killed after a lorry ploughed into crowds celebrating France's national Bastille Day in Nice.
Francois Hollande says it was a "terrorist attack" and has extended the country's state of emergency.
Safety Check automatically sends users in an affected area a note asking if they are safe.
When a user clicks on "yes, let my friends know," the tool then notifies their Facebook friends.
In a statement, a Facebook spokesperson said: "We hope the people in the area find the tool a helpful way to let their friends and family know they are OK."
Brendan Cox, widower of MP Jo Cox whose funeral was due to take place on Friday, tweeted: