Romanian police raided more houses as part of their probe of controversial influencer Andrew Tate, who is being investigated for alleged human trafficking and rape, prosecutors said on Thursday.

The British-US citizen, his younger brother and two Romanian women are under investigation for allegedly coercing women into "forced labour... and pornographic acts", which they intended to publish online for "substantial financial benefits".

Tate, 36, and his brother, 34, deny the charges, according to their lawyer Eugen Vidineac.

Seven properties in Bucharest and its surrounding areas were being searched as part of the investigation, Romania's anti-organised crime and terrorism directorate (DIICOT) said in a statement.

Tate, a former professional kickboxer, and the three others were arrested in December and ordered held for 30 days while investigations are ongoing.

DIICOT prosecutors already searched Tate's villa in April, and Romanian police raided five locations across the country in late December.

So far six potential victims have been identified.

Many of the men's assets, including their collection of luxury cars, were seized.

Just days before Tate was arrested, he had a heated Twitter exchange with Swedish activist Greta Thunberg, which went viral, on subjects ranging from cars with "enormous emissions" to pizza boxes.

In 2016, Tate appeared on the "Big Brother" reality television show, but he was removed after a video emerged showing him attacking a woman.

He then turned to social media platforms to promote his divisive views, before being banned for misogynistic remarks and hate speech.

Tate was allowed back on Twitter after Elon Musk bought the company, and his handle "Cobratate" currently has 4.5 million followers.

Tate and his brother moved to Romania several years ago.