Belgian police on Thursday raided several addresses in the country as part of a probe into alleged corruption "under the guise of commercial lobbying", prosecutors said.

Several people were held for questioning over their "alleged involvement in active corruption within the European Parliament, as well as for forgery and use of forgeries," the federal prosecutor's office said.

About 100 police officers took part in the operation that saw a total of 21 searches conducted across Belgium and in Portugal, it added.

Belgian newspaper Le Soir and investigative website Follow the Money (FTM) said the probe was linked to Chinese tech giant Huawei and its activities in Brussels since 2021.

Huawei did not immediately respond to AFP's request for comment.

The raids come more than two years after the "Qatargate" scandal, in which a number of EU lawmakers were accused of being paid to promote the interests of Qatar and Morocco -- something both countries have strenuously denied.

The prosecutor's office gave no details about the individuals or companies involved.

But it said the alleged corruption by a "criminal organisation" was "practised regularly and very discreetly from 2021 to the present day" and took "various forms".

These included "remuneration for taking political positions or excessive gifts such as food and travel expenses or regular invitations to football matches" as part of a bid to promote "purely private commercial interests" in political decisions.

The alleged kickbacks were concealed as conference expenses and paid to various intermediaries, the office said, adding it was looking at whether money laundering had also been involved.

At the heart of the alleged corruption is an ex-parliamentary assistant who was employed at the time as Huawei's EU public affairs director, Belgian media said.

Le Soir said police had taken "several lobbyists" into custody and they were due to appear in front of a judge for questioning.

None of those held for questioning on Thursday morning were EU lawmakers, a police source told AFP.

A spokesperson for the European Parliament told AFP that it "takes note of the information. When requested it always cooperates fully with the judicial authorities".