India’s southern state of Tamil Nadu has cancelled the licences of a cough syrup maker linked to the deaths of several children over the past month, it said on Monday, as authorities search some of the firm’s sites on suspicion of money-laundering.At least 19 children died in the central state of Madhya Pradesh after taking the syrup, which was banned after a test this month showed it contained nearly 500 times the permissible limit of diethylene glycol, a toxic chemical.The medicine was only...