From the BBC:

Police in southern China have discovered a factory manufacturing Free Tibet flags, media reports say.

The factory in Guangdong had been completing overseas orders for the flag of the Tibetan government-in-exile.

Workers said they thought they were just making colourful flags and did not realise their meaning.

But then some of them saw TV images of protesters holding the emblem and they alerted the authorities, according to Hong Kong’s Ming Pao newspaper.

The factory owner reportedly told police the emblems had been ordered from outside China, and he did not know that they stood for an independent Tibet.