Police have received around a dozen tips in the case of a businessman who was found dead at his home last week.

A murder investigation was launched on Friday after Koen Everink’s body was discovered by his daughter at the family home in Bilthoven, near Utrecht. Police suspect foul play but have not said if the killing was deliberate or the result of a robbery that went wrong.

On Monday a spokesman said several tips had been received, but would not disclose if they contained relevant information, NOS reports. A police helicopter surveyed the area around the house as the investigation continued over the weekend.

Police have declined to say how the businessman died. ‘That’s information about the killer, we don’t comment on that,’ said the spokesman.

Everink, 42, made his fortune in the tourism industry with the Eliza Was Here travel agency before selling his shares in 2012. The following year Quote magazine estimated his worth at €15 million.

The businessman hit the headlines in 2012 when he was badly beaten by kickboxer Badr Hari during the Sensation dance event in Amsterdam. Hari was later sentenced to two years in jail for the attack on Everink and other incidents.