The African Union has condemned a coup in Niger, where soldiers have detained President Mamadou Tandja. AU chief Jean Ping said he was watching developments "with concern" after a day of gun battles culminated in a takeover led by Colonel Salou Djibo. West African bloc Ecowas "roundly condemned" the coup and dispatched a mission to talk to the plotters. But one opposition activist told the BBC the soldiers were "honest patriots" who were fighting tyranny. Heavy artillery Mr Tandja provoked a political crisis last August when he changed the constitution of the uranium-rich country to allow him to remain in power indefinitely. The Economic Community Of West African States (Ecowas), which suspended Niger after Mr Tandja's actions, said it had "zero tolerance" for any unconstitutional changes of government. "We condemn the coup d'etat just as we condemn the constitutional coup d'etat by Tandja," Ecowas official Abdel Fatau Musa told the BBC's Network Africa programme. He said the group had already sent a team to Niger and would maintain sanctions "until constitutional order is restored". The BBC's Idy Baraou in the capital, Niamey, said on the morning after the coup, people in the city were going to mosques and shops as normal. He said there was not an obvious military presence on the streets, but heavy artillery had been deployed around the presidential palace. While state radio has been broadcasting military music overnight, state TV station Tele Sahel is continuing with live programming from a traditional wrestling championship. Freedom fighters? In a televised address on Thursday evening, a spokesman for the plotters announced that the constitution had been suspended and all state institutions dissolved. The junta, which has called itself the Supreme Council for the Restoration of Democracy, imposed a curfew and closed the country's borders. Source: BBC