The festival is regularly marred by casualties caused by sharp kite strings or celebratory gunshots fired into the air.
Kite flyers often use strings made of wire or coated with ground glass to try to cross and cut a rival's string or damage the other kite, often after betting on the outcome.
Authorities temporarily lifted a ban on kite-flying that was imposed following a string of deaths at the festival last year.
Mian Amier Mahmood, the Lahore mayor, said the two-day permission to fly kites ended on Sunday and that the ban had been re-imposed.
Police arrested more than 700 people for using sharpened kite strings or firing guns, and seized 282 illegally held weapons during this year's festival, said Aftab Cheema, a senior police officer in Lahore.
Five of those who died on Sunday were hit by stray bullets, including a six-year-school boy who was struck in the head near his home in the city's Mazang area, Bano said.
He also said that a 16-year-old girl and a school boy, 12, died after their throats were slashed by metal kite strings in separate incidents.
Two people were electrocuted while they tried to recover kites tangled in overhead power cables.
A 13-year-old boy fell to his death from the roof of his home as he tried to catch a stray kite, and a 35-year-old woman fell off the roof of her home trying to stop her son from running after a stray kite.