FILE PHOTO: The logo of Swiss bank Credit Suisse is seen at its headquarters at the Paradeplatz square in Zurich, Switzerland October 1, 2019. REUTERS/Arnd Wiegmann/File Photo

ZURICH (Reuters) - A private investigator from the firm tasked with tailing former Credit Suisse CSGN.S banker Iqbal Khan has countered Khan's legal action with criminal complaints against the banker, his wife and the police, Swiss prosecutors said on Wednesday.

Khan, who left Credit Suisse in July to became rival UBS's UBSG.S co-head of wealth management, filed a criminal complaint in Switzerland following a confrontation with private detectives tailing him and his wife on Sept. 17.

The scandal led to an investigation by Switzerland’s bank watchdog into Credit Suisse’s conduct and criminal proceedings in Zurich which remain ongoing.

The Swiss Investigo detective agency which was hired to follow Khan has said the ensuing publicity caused it severe reputational and financial damage.

An Investigo employee has since submitted a criminal complaint against Khan and his wife to the state prosecutors office handling the criminal proceedings, a spokesman for Zurich prosecutors said, adding that the complaint was under review.

The prosecutors said they were also reviewing a separate criminal complaint by the Investigo employee against members of the Zurich police lodged shortly before Christmas, but declined comment on the specific accusations made in both complaints.

A legal representative for Khan said he stood by his version of events. Investigo did not respond to an emailed request for comment.

A spokesman for Zurich’s local cantonal police declined to comment on the complaints, which were first reported by Swiss newspaper Tages-Anzeiger earlier on Wednesday.