Sawant, who was a local leader from Kurar in Maharashtra, was shot in the chest and was declared brought dead, according to doctors at Shatabdi Hospital in Kandivali.
He was a former deputy branch head of the Shiv Sena from Kurar.
A police investigation is underway.
This is the third incident of this month where a Shiv Sena leader was targeted.
On April 7, two Shiv Sena leaders were shot dead by two men on a motorcycle in Ahmednagar's Kedgaon area after the result of a civic bypoll was announced.
The deceased were identified as Sanjay Kotkar and Vasant Anand Thube. (ANI)