Authorities said they suspected a faction of the banned United Liberation Front of Assam (ULFA) of carrying out the killings on Thursday, as well as a bomb attack in the state’s largest city, Guwahati, last month.
ULFA rebels, who want a breakaway homeland for ethnic Assamese people, have threatened attacks over proposed amendments to India’s citizenship law that would grant citizenship to Bengali-speaking Hindus.
Gunmen in military fatigues entered the village in Tinsukia district and ordered ethnic Bengalis out of their home, officials said.
Four people were killed on the spot and a fifth died in hospital, they said.
ULFA chief Paresh Baruah recently threatened Bengalis who wanted to stage a rally in support of the citizenship amendment bill being pushed in parliament by the right-wing Bharatiya Janata Party (BJP).
The bill aims to give citizenship to Hindu, Sikh, Buddhist and Christian minorities from India’s neighbouring countries who arrived in the country before 2015.
Activists and opposition leaders say the bill discriminates against Muslims and violates the secular constitution of India.
Political and social groups in Assam have accused the BJP of seeking to use the law to naturalise citizenship of Bengali-origin Hindus to get their votes.
Assam Chief Minister Sarbananda Sonowal said “strong action” would be taken against the killers, but he also appealed for calm.
Assam’s migrants question
The state of Assam has been rocked by protests over undocumented immigration from Bangladesh for decades.
India this year published a provisional list of people in Assam eligible for citizenship, called the National Register of Citizens (NRC), in a bid to identify undocumented migrants from Bangladesh.
The draft list effectively stripped nearly four million people of the 32 million in Assam of their citizenship.
Those who proved they came to the state by March 24, 1971 – the cut off date to be eligible for Indian citizenship – were included on the NRC.
The people whose names were not included on the NRC have been allowed to file their claims and objections by December 15.
Experts, meanwhile, say it will take several years to produce a final version of the list.
Bengali Muslims still fear they could be deported while rights groups have said there could be attacks on Assam’s ethnic minorities.
In February 1983, more than 2,000 Bengali-speaking people were killed in Nellie in central Assam. In recent years, hundreds of people have been thrown in detention camps in the border state.
Read more: India: Suspected separatists shoot dead five in Assam | India News | Al Jazeera