Kathmandu, April 5 -- A widening money laundering investigation following the arrest of controversial businessman Deepak Bhatta has drawn one of Nepal's oldest corporate houses, the Shanker Group, into its net.

The group's chairman Shanker Lal Agrawal has already been detained, while police are searching for his sons. Investigators have also brought individuals linked to the group under scrutiny as the probe gathers pace.

More than 40 businesses operated by the group across the country are likely to be directly affected. The conglomerate has an annual turnover of over Rs125 billion and employs more than 15,000 people. Banking sources estimate that companies under the group have borrowed close to Rs200 billion from banks and financial in...