Officials from Britain’s Serious Fraud Office (SFO) have launched a multi-million pound international bribery investigation connected to the construction of a Microsoft data centre in the Netherlands.

The case centres on the UK-based company Blu-3 and former associates of the global construction firm Mace Group. Individuals at Blu-3 are suspected of paying more than £3 million in bribes to former Mace associates in relation to the construction project, the SFO said in a statement. Microsoft is not involved in the investigation.

Microsoft operates a large data centre in the Noord-Holland local authority of Hollands Kroon and was cleared by the Council of State to begin construction of a second facility in the area a year ago. Both Blu-3 and Mace are involved in that project.

So far, three people have been arrested in the course of the British investigation, the SFO said in a statement. Several properties in Britain and one in Monaco have been searched.

Mace said it has a “zero tolerance approach to breaches of our code of ethics, and takes any allegations of bribery extremely seriously”.

“We are committed to fully supporting the Serious Fraud Office in investigating allegations against any former associates of the group,” the company said.

Hollands Kroon council has so far declined to comment. Last year, consultancy firm Berenschot published a council-commissioned report evaluating its data centre strategy, which has drawn criticism from local residents and environmental groups.

The report concluded that the council should have communicated more proactively with the public, but found no “legal, financial or other formal wrongdoings” in its decision-making process. It also said the local authority’s approach to data centre development had remained “consistent” over time.