Trade union officials said the men would not be allowed leave until Goodyear agreed to improved redundancy packages.
Workers at a troubled Goodyear tyre factory in northern France were holding two managers hostage for a second day on Tuesday in a dispute over planned job cuts.
Production manager Michel Dheilly and human resources manager Bernard Glesser have been held in a meeting room at the plant in Amiens since Monday morning. One of the entrances to the room has been blocked with a giant tyre.
Trade union officials said the men would not be allowed leave until Goodyear, which announced plans last year to close the plant with the loss of up to 1,173 jobs, had agreed to improved redundancy packages.
The two men had food and drink and were in constant contact with their families by mobile phone, a spokesman for the CGT trade union said.
Goodyear slammed the protest and said it would not negotiate with the workers until the two managers were released.
“Bossnapping” — as the act of workers taking their bosses hostage has been dubbed — is not uncommon in France.
In 2009, managers at several big firms, including Caterpillar, 3M and Sony, were held by staff for short periods in disputes over job losses or redundancy packages.