The family live in the Cameroonian capital, Yaounde, where the father worked for the French gas group Suez.

BBC: French children kidnapped in Cameroon 'shown in video'

He is also the biggest shareholder in France's fourth-biggest industrial group, Suez Lyonnaise des Eaux, with about 11.5%.

ECONOMIST: Closing the deals

The French gas group GDF Suez identified the captives as an employee working in the Cameroon capital of Yaounde and his family.

NPR: Cameroon President Orders Urgent Rescue Of French

Without a merger, Suez's managers in the group's central holding company would have found it increasingly hard to justify their existence (after all, Suez's subsidiaries, most of which are public firms, largely run themselves).

ECONOMIST: Suez and Lyonnaise des Eaux

Just ask Suez-Lyonnaise des Eaux, a French finance and utilities group.

ECONOMIST: Tractebel the intractable