2016 Brussels bombings
People shared cartoons and showed sadness in black, yellow and red, the colors of the Belgian flag. Others put messages of solidarity with #JeSuisBruxelles, or "I am Brussels," an ode to a similar outpouring with #JeSuisCharlie after the Charlie Hebdo attack in January 2015. Some people invited tourists stuck after the airport was shut into their homes using #OpenHouse.