Vietnamese police detained scores of people as they broke up a protest against a Taiwanese company accused of being behind a toxic leak that has caused mass fish deaths off the central coast. The protest in Hanoi, which follows a similar demonstration last weekend, was swiftly dispersed by authorities on Sunday morning, an AFP reporter witnessed, in a communist country where all shows of dissent are tightly controlled. Several hundred demonstrators had gathered in the heart of the capital outraged at the poisoning of waters near Ha Tinh province that has left tonnes of fish and clams dead and decimated the local fishing industry, accusing Taiwanese steel mill Formosa of overseeing a toxic leak.