French president Nicolas Sarkozy has vowed to stamp out "boss-napping"
Three British bosses held hostage by workers at an adhesives factory in France over plans to close the site have been released.
The executives and a local manager, who were captured at British firm Scapa on Tuesday night, were allowed to leave the site to resume talks elsewhere.
Over 60 employees face redundancy at Bellegarde-sur-Valserine, near Lyons in south east France.
There have been a number of similar incidents in France over recent weeks.
Scapa's European finance director Ian Bushell said unions representing staff carried out the "non-aggressive" action at the firm, which manufactures adhesive tape for the car industry.
The company has been in talks about the plant's closure since the end of January. The negotiations broke down on Tuesday and unions refused to allow the managers to leave the site.
At one point a lorry was used to block the plant's entrance, Mr Bushell said.
Workers took four executives hostage in Bellegarde-sur-Valserine
Meanwhile, French president Nicolas Sarkozy has vowed to end the practice of "boss-napping" after militant workers targeted four factories in the past month.
He said the practice was "totally unacceptable" and warned people found guilty would face prosecution.
Mr Sarkozy said: "What is this business of sequestering people? We have the rule of law, and I will not let matters go on like that.
"We can understand that people are angry, but this anger will subside with answers and results, not by aggravating matters with actions that are contrary to the law.
"I am insisting the police and courts arrest and prosecute those workers who take the law into their own hands in this way."
Over the past month, employees at French plants belonging to Sony, Caterpillar, 3M and German auto-parts maker Continental have held bosses captive.
It is not a new tactic but has gained more prominence in recent weeks as firms affected by the economic downturn announce job losses and plant closures.
Usually executives are released within a day or two, often after unions have extracted concessions.
Scapa, which is based in Ashton-under-Lyne, Greater Manchester, employs 1,300 people worldwide and 238 staff in France at three sites, including Bellegarde.
The company's chief executive Calvin O'Connor said that the sharp downturn in the car industry meant the Bellegarde site had to close.
Mr O'Connor said negotiations at local government offices on Wednesday afternoon appeared to have made some progress. He confirmed that the executives were all able to return to their homes in France after the meeting.
He expects talks about the plant's closure to resume on Thursday.