A power cut plunged the whole of Hanover in northern Germany into darkness for 40 minutes late on Wednesday, authorities said, sparking chaos in the city of more than half a million people. Around 350 rescue workers were called out after the power went off at 10:35 pm (2035 GMT), setting off fire alarms, leaving people stuck in lifts and hospitals and old people\'s homes scrambling to activate backup systems. \"We had 750 emergency calls,\" Jan Feichtenschlager, a spokesman for the fire brigade, told AFP. Hanover\'s airport was also hit but no flights were affected, it said. Power was restored to 70 percent of the city within 40 minutes and to the rest after an hour and three-quarters. Engineers are looking into the cut, caused by an important piece of equipment at a nearby power station breaking. The incident came five days before the start of a 24-hour visit to Hanover from from late Monday by Russian President Dmitry Medvedev when he will hold talks with German Chancellor Angela Merkel.