The two injured were rushed to Guwahati Medical College and Hospital. The official death toll in the ongoing clashes, which began last month, is now 64.
Bishnoi said that the three killed belong to Lakhiganj of bordering Dhubri district.
Following the incident, a curfew has been clamped again in Kokrajhar district while indefinite curfew continues in the neighbouring Chirang district where there are fresh reports of arson.
Some houses were burnt down there but the timely action of police prevented any major violence last night, Bishnoi said.
One person has been arrested in this connection from Chirang.
The army continued their flag march on Tuesday morning in the three districts of Kokrajhar, Chirang and Dhubri, hit by clashes between Bodo tribals and the minority community.