Incessant torrential downpour killed four persons, including a 53-year-old bedridden paralysed woman, in Nagpur, police said on Saturday.Earlier today, it has been reported that water gushed into homes and residential areas inundating several roads as the city received about 90 mm of rain between 2 am and 4 am.So far, over 400 people, including 70 students from a school for the speech and hearing-impaired, were rescued.