A tussle between the chief of the Central Bureau of Investigation versus his number 2 - dubbed Prime Minster Narendra Modi's "blue-eyed boy" by Congress chief Rahul Gandhi - is seen as the trigger for a crisis within the agency and brought it under spotlight. After tit-for-tat allegations of bribery, a First Information Report and a letter to the Cabinet Secretary, an officer involved in the investigation of a case central to the crisis has now been arrested and the two top officers have been summoned by PM Modi.
Despite repeated opposition attacks, the government had initially refused to step in, citing the autonomy of the agency. The opposition attacks have continued.
Today, calling the CBI an "institution in terminal decline at war with itself", Congress chief Rahul Gandhi tweeted, "The PM's blue-eyed boy, Gujarat cadre officer, of Godra SIT fame, infiltrated as No. 2 into the CBI, has now been caught taking bribes. Under this PM, the CBI is a weapon of political vendetta".
Insiders say the rivalry between the two officers dated back to the time when there was talk of Rakesh Asthana being elevated to the agency's second highest post in October last year. Alok Verma had written to the authorities, pointing out that Mr Asthana was being investigated in a bribery case allegedly involving Gujarat-based firm Sterling Biotech.
A 1984-batch officer of the Gujarat cadre, Mr Asthana held key posts in the state and received assignments directly from Mr Modi, who was the Chief Minister of the state. He headed the state's Special Investigation Team that probed the burning of Sabarmati Express in Godhra in February 2002.
When Mr Modi took over as the Prime Minister, Mr Asthana was one of the Gujarat officers handpicked for a move to Delhi.
Transferred to the Central Bureau of Investigation, he was put in charge of a string of crucial cases - including the ones involving fugitive tycoon Vijay Mallya, Sonia Gandhi's son-in-law Robert Vadra, the Aircel Maxis case, the VVIP chopper deal and the coal scam case.
In December 2016, he was made the interim chief of the CBI after the retirement of Anil Sinha - a move against which lawyer-activist Prashant Bhushan had approached the Supreme Court, pointing to his lack of seniority.
There was speculation that the government wanted Mr Asthana to fill in the top post till he was senior enough to be given a more permanent role. Mr Asthana will be eligible to be considered for the top post next year.
When senior Congress leader Mallikarjun Kharge, too, challenged the appointment, the government said it had made an interim appointment since the selection committee led by PM Modi hadn't had time to meet.
Compared to Rakesh Asthana, Alok Verma -- a 1979 batch IPS officer of the AGMUT (Arunachal Pradesh-Goa-Mizoram and Union Territory) cadre - is seen as having a low profile.
The officer has served as the Director General of Tihar jail and the Chief of Delhi Police before he took over as the chief of the Central Bureau of Investigation.
Lately, he is said to have upset the Centre by meeting politicians like Yashwant Sinha and Arun Shourie over the Rafale 36-jet deal with France.
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