In the wake of communal violence in Assam that killed more than forty people—most, if not all of them, Muslims—Narendra Modi, the prime ministerial candidate of the official opposition Bharatiya Janatha Party (BJP), has amplified his communally-charged denunciations of Bangladeshi Muslim migrants to India’s north-east.

Speaking at an election rally in West Bengal last Sunday, Modi railed against Muslims migrants from Bangladesh and repeated his oft-repeated election vow that a BJP government will expel them.

The virulently communalist character of Modi’s speech was underlined by the distinction he drew between Hindu and Muslim migrants from Bangladesh. While he called the former “our brothers” and promised that they would be extended citizenship rights, he denounced the latter, adding that his political opponents were favoring Bangladeshi Muslims for electoral gain.

“Those,” said Modi, “who are forced to flee Bangladesh and are sons of mother India, love the nation, worship [the Hindu goddess] Ma Durga, speak Bengal … they will be protected and given the same status as other sons of mother India. But illegal Bangladeshi migrants, who are being brought to India in the name of vote-bank politics, will have to go back to Bangladesh,”

Continuing in this ultra-reactionary vein, Modi denounced the BJP’s principal electoral rivals in West Bengal, while seeking to blame Bangladeshi Muslim migrants for the state’s mass joblessness: “Instead, of making sure that the youths of our nation are employed, the Congress [Party], the CPI (M) [Communist Party of India (Marxist)] and Didi [West Bengal Chief Minister and Trinamool Congress head Mamata Banerjee] have ensured that Bangladeshi migrants get jobs to develop them as vote bank. Those who snatch away job opportunities of our youths will have to return.”

Modi’s remarks—which he has since repeated at other election rallies—were his reply to charges from some of his political opponents that he and the Hindu supremacist BJP bear some of the responsibility for last week’s massacre of Muslim villagers in Assam, since they have made denunciations of Bangladeshi Muslim migrants pivotal to their election campaign in India’s north-east.

Beginning last Thursday, gunmen, believed to be Bodo national-ethnic separatists, mounted a series of attacks on Muslim villagers, including women and children, in the Baksa and Kokrajhar districts of Assam. The violence continued until Saturday and left at least 41 people dead.

Fearing further retaliatory attacks, both Bengali-speaking Muslims and Bodo tribals have fled from their homes. While Muslims from Kokrajhar have fled to the predominantly-Muslim adjacent district of Dhubri, Bodo families have fled Dhubri to Kokrajhar, which is one of four Assamese districts that partly fall under the jurisdiction of the Indian government-established Bodoland Territorial Council.

Assam’s Congress state government deployed security forces, including Indian army personnel, to the violence-affected districts and Chief Minister Tarun Gogoi is urging the central government to send additional troops.

The attacks are believed to have been launched by the National Democratic Front of Bodoland (NDFB), a separatist movement waging an armed campaign for a “sovereign Bodoland.” The Bodo separatists accuse Bengali-speaking Muslims—from both Bangladesh and the Indian state of West Bengal—of encroaching on Bodo ancestral lands. Communal clashes involving Bodo tribesmen and Bengali-speaking Muslims in the same area in July-August 2012 led to the killing of over a hundred people and the displacement of more than 400,000. This was reputedly the largest population displacement in India since the 1947 communal partition of the Indian subcontinent.

Both the Congress Party and Mamata Bannerjee and her Trinamool (Grassroots) Congress have blamed the BJP’s rank communal appeals for the escalation of communal strife in Assam. In this they point not only to Modi’s inflammatory speeches, but also to the Assam BJP’s pledge—spelled out in its election manifesto—to identify and expel all Muslim migrants from Bangladesh.

Congress leader Kapil Sibal has charged that the violence in Assam was a result of the “communal polarization” that BJP and Modi have promoted in the north-east so as to garner votes.

On Monday, Mamata Banerjee told an election rally in Krishnagar that Modi is seeking to incite communal and caste-based violence: “We are telling the Election Commission that he should be arrested and should not be allowed to campaign in” West Bengal.

That Modi and the BJP have blood on their hands is without question. They have a decades’ long history of promoting communal violence. They have mounted their vile campaign in Assam with the aim of inciting hatred against the state’s Bengali-speaking Muslim residents and done so knowing full well that it could end in bloodshed.

But the Congress Party and Banerjee are not without their share of the blame. They have adapted to and connived with the Hindu communalists. They will denounce the BJP for its virulent communalism when they view it as politically, especially electorally, advantageous, but at other times they lend the BJP and its Hindu nationalist appeals legitimacy.

The traditional party of the Indian bourgeoisie, the Congress Party collaborated with Indian’s departing British colonial overlords and the Muslim League in partitioning India into a Hindu-dominated India and a Muslim Pakistan.

Bannerjee was a partner of the BJP in the BJP-led National Democratic Alliance (NDA) government from 1999 to 2001, serving as its Railway Minister. And for the 2004 national election, the Trinamool Congress returned to the NDA fold.

The tensions between Bengali-speaking Muslims and Bodo tribesmen in Assam have their roots in the bourgeoisie’s suppression of the mass anti-imperialist movement that convulsed India in the first half of the Twentieth Century, as exemplified by the 1947 Partition. Bengal in defiance of its history and economic logic was sundered with West Bengal becoming an Indian state and East Bengal becoming East Pakistan, which broke away from Pakistan and became Bangladesh in 1971.

The Indian bourgeoisie’s neglect and repression of the tribal peoples of north-east India has helped fuel ethnic separatist movements among them, including among the Bodo. The Bodo separatists seek to carve an ethnically-defined nation-state, Bodoland, from Assam. They exploit genuine democratic and social grievances, but, as their foul communal-exclusivist attacks on the Bengali Muslims underscore, offer no progressive alternative to Indian bourgeois rule. They represent not the Bodo people, but rather the interests of a tiny Bodo elite that wants a separate enclave for exploiting their “own” Bodo working class and the region’s natural resources and to strike their own deals with international capital.

As a part of their reactionary separatist program of dividing working people and rural toilers along ethnic and religious communal lines and boosting the interests of the tiny Bodo elite, the Bodo separatists work to pit impoverished Bodo tribesmen against similarly downtrodden Bengali-speaking Muslims.

Bangladesh’s government has not issued any official statement in response to Modi’s denunciations of “illegal Bangladesh immigrants,” no doubt because it doesn’t want to be accused of interfering in India’s election campaign. However the Economic Times has reported that Bangladesh Prime Minister Sheikh Hasina has expressed concerns over Modi’s statements “telling her close aides in a private meeting” that Modi’s comments are “unnecessary and unwarranted” and “could spoil relations between the future Indian government and Bangladesh citizens”.

Modi’s denunciations of Bangladeshi Muslim migrants and his decision to amplify them in the wave of the communal massacre in Assam have grave implications for India and the region.

There is no doubt that Modi and the BJP have used the Bangladeshi migrant issue as a means of appealing to the BJP’s Hindu nationalist cadre across India and to promote their noxious Hindutva ideology—which maintains that India is first and foremost the holy land and homeland of the Hindus—without being seen to directly attack India’s Muslim minority.

Should the BJP come to power as a result of the current election, as many are predicting, and seek to make good on its pledge to expel “Bangladeshi Muslims” from India it would, as Hasina’s not for accreditation remarks indicate, fuel tensions with the Bangladesh government. It could also lead to further communal attacks by Muslim communalists on Bangladesh’s Hindu minority.

BJP spokesman have claimed that there are as many as 20 million “illegal” Bangladeshi migrants in India.