Large areas of northern India are sweltering under the longest heatwave on record,triggering widespread electricity outages and angry protest over the government's failure to provide basic services.The heatwave, which some activists say has caused dozens of deaths,is one of the first major challenges for Prime Minister Narendra Modi,who made reliable electricity supplies one of his campaign pledes.In Delhi,where temperatures hit 45 celsius for six days straight,residents marched in protests organised by opposition parties.In the north of the city,people enraged by night-long outages clashed with police and torched a bus.Modi has inherited the power shortages from his predecessors,and power distribution is partially the responsibility of state governments.