Officials were keeping a vigil on a factory at Coonoor in neighbouring Nilgiris District since last evening following information that 10 tonnes of adulterated tea would transported to Bangalore through the city.
They followed a lorry in which the tea bags were loaded from the factory till being unloaded in a godown in Thudiyalur and seized the bags, officials said.
An additional 10 tonnes of tea, already stored in the godown were also seized, they said.