NIGERIA television and radio stations should not use Twitter to gather information and have to de-activate their accounts, the broadcast authority said following the move to suspend the U.S. social media giant in Africa's most populous country. Nigeria's government on Friday said it had suspended Twitter's activities, two days after the platform removed a tweet by President Muhammadu Buhari that threatened to punish secessionists. Nigerian telecoms firms have since blocked access to Twitter. International diplomats responded with a joint statement in support of "free expression and access to information as a pillar of democracy in Nigeria". Buhari, who was Nigeria's…