LONDON: Three British executives were taken hostage by militant workers in France hours after the French President, Nicolas Sarkozy, pledged to outlaw what has become known as "boss-napping".

Th e three managers and a French colleague were detained at the factory in Bellegarde, in the foothills of the French Alps, when negotiations over terms of the plant's closure broke down on Tuesday.

Workers blocked the entrance to Scapa Group site with a truck, said the company's European finance director, Ian Bushell.

The Scapa plant, which employs 68 people, makes adhesive tape for the vehicle industry. Plans to close the plant were drawn up in response to a car market suffering its worst crisis in decades.

Mr Sarkozy pledged to end the spate of boss-nappings that have plagued France since the start of the recession.

"What is this business of kidnapping people?" he said. "We abide by the rule of law, and I will not let this carry on. We understand that people are angry but this anger will subside with answers and results, not by aggravating matters with actions which are against the law."

Last week militants in Paris held the head of Gucci, Francois-Henri Pinault, captive in a car for an hour in protest against 1200 job cuts.

The attempted abduction was the fifth in a month.

Almost half of French people sympathise with the militant action, a poll published this week found.

Lilian Mathieu, a sociologist at the Paris-Sorbonne University, said: "Even if [hostage taking] rarely succeeds in reversing a redundancy plan, the challenge is to leave on more favourable terms, to wrench some last-minute concessions."

Guardian News & Media, Telegraph, London