Changes to a Belgian telecoms firm’s router software are believed to be the result of a cyber attack.

Belgacom has found changes made to its router software at its communication services provider division BICS after hackers targeted the firm’s corporate network last month.

According to the company, the irregularities were detected during the aftercare monitoring process carried out on all systems following the attack.

Belgacom has increased control and prevention measures since, and the company said that all available information is being shared with the investigators and competent authorities, who are pursuing the judicial inquiry.

"In collaboration with external experts, and in consultation with the investigators in charge of the judicial inquiry, the specialists of Belgacom and BICS are continuing the investigation, and remedial actions are also being prepared," the company said.

"The competent authorities, the BIPT and the Privacy Commission, were informed and will continue to be updated."