Facebook has activated safety check option for people in Dhaka, so they can let their friends and family know if they are safe after terrorists took hostage at a Spanish restaurant in the Gulshan diplomatic zone.In an unprecedented turn of events on Friday night, gunmen held hostage dozens of people inside a popular hangout for foreigners in the capital’s diplomatic zone of Gulshan, and fired shots and hurled bombs at law enforcers.After 12 hours, army commandoes brought to end the hostage situation, rescuing at least 13 people.