Vanlalhriata pushed Abhinaba Bag on the left side of the corner flag and then picked up arguement on being fouled, forcing the referee to flash the red card.
"It may lead to one match suspension; but the technical committee will decide about it," said a technical official.
Bengal drew the first blood when Sakar Sil, after getting a through pass, bulged the Mizoram net in the 38th munite to make it 1-0.
Mizoram restored parity when Zico Zoreushanga stabbed the leather from close eleven minutes after the breather.
Substitute Gautam Thakur and Dipindu Biswas mounted several openings but poor finishing eluded them to increase the margin.