The CBI has sealed PNB's Brady House branch in Mumbai where the $1.77 billion fraud involving jewellers Nirav Modi and Mehul Choksi originated. CBI is also questioning Vipul Ambani, the CFO of Nirav Modi's company Firestar International. The agency has interrogated 5 more bank officials, including general manager-level officers, taking the total number of officials facing questioning to 11.