BERLIN -- Tens of thousands of employees from Germany's metalworking sector and electrical industry downed tools Thursday on the first day of a warning strike over pay, a union said.

Powerful union IG Metall said that nearly 50,000 workers across 100 plants had heeded its call for a temporary stoppage and announced more action across the country in the coming days.

The southwestern state of Baden-Wuerttemberg was most affected, with 26,500 workers having taken part in Thursday's strike, including some at auto makers Daimler and Porsche.

The union is calling for a 5.5% salary rise this year for 3.7 million metalworkers spread across different branches ranging from automobiles to electronics.

Several rounds of negotiations have taken place with the employers' federation, Gesamtmetall, which early last week offered a 2.3% rise for 11 months from July 1.

IG Metall rejected the offer.

Pay talks in the metalworking sector set the tone for other areas of industry.

Copyright Agence France-Presse, 2013