Just as India's banks emerge from under a pile of bad loans to large energy, steel and other industrial companies, they are facing a new reckoning from the accelerating crisis in the country's shadow banking sector.

A year after a series of defaults by Infrastructure Leasing & Financial Services Ltd. forced the government to intervene and exposed weaknesses in the sector, the problems of India's non-bank financial companies are entering a new phase. Other weaker lenders such as Dewan Housing Finance Corp. and Anil Ambani's Reliance Capital Ltd. are struggling, putting the loans they received from a handful of the regulated banks at risk.

"There will be some defaults, some additional slippages on banks' books from the NBFC sector and that will be reflected in the performance of some of the bank stocks, which are more exposed to the weak NBFCs," said Suresh Ganapathy, an associate director overseeing financial research at Macquarie Capital Securities in India.