Over 20 places are being searched in Bengaluru and also in other cities like Mumbai and Chennai, say reports.
Taxmen are reportedly also searching the estates in Chikmagalur of Coffee Day Enterprises, which is India's largest coffee retail chain. VG Siddhartha is said to be among the country's largest exporters of coffee bean.
84-year-old Mr Krishna's crossover from the Congress - his party for decades - to the BJP, signaled a big political move ahead of the Karnataka polls next year.
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