India's markets regulator has widened an investigation into alleged market manipulation by U.S. securities trading firm Jane Street to include other indexes and exchanges, a source familiar with the matter said.

Jane Street's strategy involved large-scale purchases of Bank Nifty futures and equities in the morning, paired with aggressive selling of Bank Nifty options. This would be followed by significant selling in the futures market post-noon,

India’s regulator has temporarily barred Jane Street from accessing the local securities market, dealing a severe hit to the US firm that allegedly made $4.3 billion in trading gains in the South Asian nation in more than two years.