Jewellers in Ahmedabad were baton-charged when they tried to block traffic on busy Sarkhej-Gandhinagar highway.
Protesting traders blocked traffic in Vadodara, Surat, Rajkot.
Bullion markets in Chennai, however, remained open for regular trading.
Jewellers are protesting a hike in import duty and excise duty on unbranded jewellery.
They have gone on strike ever since the Finance Minister Pranab Mukherjee in his Budget on March 16 proposed one per cent excise duty on unbranded jewellery and doubling the import duty to 4 per cent on gold.
The strike entered the 18th day on Tuesday.
With traders' associations
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