West Bengal's chief minister, Mamata Banerjee, alleges that Modi is interfering in the affairs of her state. Critics claim that the premier is using intelligence agencies to harass opponents ahead of general elections.
Constitutionally, India is a "union of states" and follows a federal structure of government. This means that while some functions and institutions are subordinate to the government in New Delhi, many others are managed by state governments. Recently, however, the central government under Prime Minister Narendra Modi has been accused of overstating its authority and getting in the way of state governments.
A particularly strong allegation has emerged from West Bengal, where Chief Minister Mamata Banerjee (main picture) has alleged that Modi is trying to "stage a coup" and usurp power in her administrative area through indirect means. The minister is meanwhile on strike in Kolkata, the state capital, and has said that her agitation aims to "save democracy, the constitution and the country."
"The highest levels of the BJP leadership are doing the worst kind of political vendetta," Banerjee said in a tweet, adding: "They are misusing power to take control of the police and destroy all institutions."
The Saradha 'chit fund' scam
The latest controversy was triggered after the Central Bureau of Investigation (CBI), which investigates high-profile crimes involving finances, corruption and communal harmony, was charged with recovering documents from Kolkata related to a financial scam concerning the Saradha Group, which operated a consortium of 200 private companies and robbed nearly 2 million people of around $6 billion (€5.24 billion).
The company used the so-called Ponzi scheme and later used money taken from investors to pay people who had invested early on in the project. Millions of people from India's lower-middle class paid small sums of money into the scheme.
After the scandal was exposed, two officials of the group were arrested and the state government offered some financial relief to low-income investors. An official investigation was launched in 2013 and the case was handed out to the CBI in 2014.
On February 3, the CBI said it wanted to question the chief of Kolkata's state police, Rajeev Kumar, about the progress in investigations concerning the scam. However, Kumar's guards prevented CBI officials from entering the building, causing scuffles that eventually lead to the arrest of the CBI investigators.
Kolkata has meanwhile accused the CBI of trying to invade the police commissioner's office without any warrants or documentation justifying their actions. The CBI, in turn, says it did have the necessary papers and accuses the police commissioner of destroying crucial evidence related to the case.
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On Monday, Indian Home Minister Rajnath Singh condemned the incident saying, "A clash like this, between law enforcement agencies, is not only unfortunate but is also dangerous for the country's federal and political system."
The CBI has been stepping up its investigation into the case, prompting allegations that the central government under Narendra Modi is trying to malign the West Bengal government before general elections in May. Federal governments in India have often been accused of compromising the independence of the CBI.
Last year, the bureau's autonomy came under question again, when a disagreement between the bureau's former chief, Alok Verma, and his deputy, Rakesh Asthana, became public and Verma was removed from his position. Opposition parties accused the government of removing the former chief for his investigation into a billion-dollar fighter jet deal between New Delhi and Paris. Meanwhile, Rishi Kumar Shukla has been named the new head for the investigating body.
Modi's party, the Bharatiya Janata Party (BJP), is an opponent of the Trinamool Congress, which under Banerjee administers the state of West Bengal. The CBI accuses the Trinamool Congress of being involved with the Saradha scam, hinting at the possibility that the standoff may be more about the enmity between the two parties rather than an earnest attempt at resolving the case.
With general elections round the corner, both parties have continued to accuse each other of attacks, with the TMC charging the Modi government of stifling democracy in India. BJP members in turn, have demanded that the centre enforce president's rule in the state, effectively withdrawing all administrative power from Banerjee and her party.
The BJP and the TMC have been at loggerheads regarding several issues in the past. Latest issues include the TMC's protest against demonetization, which the Modi government undertook in late 2016 and the General Sales Tax (GST) that was introduced last year.