At least 12 deaths have been reported in a swine flu outbreak across four Indian states, dpa quoted health ministry officials as saying Friday. The outbreak has affected a total of 129 people since the beginning of March and many of the patients were still hospitalized, health ministry spokeswoman Shefali Saran said. The western state of Maharashtra was the worst hit, with six deaths in and around Pune, the state's second-largest city after Mumbai. Five people died of the virus in the north-western state of Rajasthan while one person died in southern state of Andhra Pradesh, data released by the ministry showed. Another southern state, Karnataka, confirmed five cases of the H1N1 virus. Saran said the situation was "under control and there was no panic." The health ministry had asked state authorities to step up surveillance to stop the spread of the disease," Saran said. Officials said it was not immediately clear why there was a sudden outbreak of the disease. "Last year globally, swine flu was at an ebb," National Institute of Virology director AC Mishra told The Indian Express daily. "While short spurts are being recorded in other countries this year, it could well be a short spell where the virus will surge and then die down," he said. More than 1,800 people have died of swine flu across India since May 2009, most of them during an outbreak during that month, according to Health Minister Ghulam Nabi Azad.