Around the same time, Rakesh Gargunde, a doctor with the Civil Hospital in Nashik city, also succumbed to the flu, said civil surgeon A.D Bhal Singh.

Gargunde was admitted to hospital in an unconscious state two days ago and put on a ventilator. The test report confirming that he had swine flu was received by the hospital late Tuesday.

Wednesday saw the highest number of deaths in a day since the first victim, Reeda Sheikh, 14, died in Pune Aug 3.

At least four patients continued to be in a serious condition at the Sassoon hospital, Pune District Collector Chandrakant Dalvi told reporters.

In Mumbai's Hiranandani Hospital, two swine flu patients were in serious condition.

Pune has already been declared an epidemic city, while the Maharashtra government has announced unprecedented measures across the state to contain the spread of the deadly virus.

While Maharashtra accounts for 13 deaths -- 10 in Pune, two in Mumbai and one in Nashik - one death each has been reported from Vadodara, Ahmedabad, Thiruvananthapuram and Chennai.