French engineer Eiffage has won a €1.3bn contract to build a headquarters for France’s General Directorate for Internal Security (DGSI), the country’s counter-espionage and counter-terrorism agency.

Reporting the award, news site Intelligence Online described the procurement process as “long and secretive”.

DGSI plans to move from the Levallois-Perret district in northwestern Paris to a 6ha site in neighbouring Saint-Ouen.

Demolition of buildings on the site has begun with a view to completing the project by 2028.

Nicolas Lerner, the director-general of the agency, considered around 20 sites before selecting Saint-Ouen, DGSI said, with this one offering the best security, cost and adaptability to the agency’s needs and its way of working.

It added that the urban improvements brought by the Olympic Games were an advantage, including improved transport links and the use of the athletes’ village as a base for some 2,500 agents of the Ministry of the Interior.