An extraordinary corporate espionage scandal has deepened at Credit Suisse after the Swiss bank admitted a second executive had been tracked by private detectives.

The bank has confirmed that its former head of human resources Peter Goerke was followed for “several days” in February this year by private detectives hired on behalf of the bank. This follows the revelation that Iqbal Khan, the former head of the bank’s wealth management division, had been chased by investigators through the streets of Zurich in September.

Credit Suisse insisted at the time that the Khan incident was a one-off and that its chief executive, Tidjane Thiam, had no knowledge of it. However, on Monday it confirmed the second case involving Goerke and once again cleared Thiam of any responsibility.

It is understood that the surveillance of Goerke was conducted after he was told he was being bumped off the executive team and demoted to a senior adviser role, which he still holds.

The former chief operating officer Pierre-Olivier Bouée has been blamed by the bank for both incidents. He resigned in October after the Khan incident was uncovered.

Khan was trailed for several days in September, shortly after he left the bank for a rival position at UBS. Relations had reportedly soured with Thiam, culminating in a dispute over landscaping at their neighbouring properties on Lake Zurich.

Private detectives followed Khan through the streets of Zurich, resulting in an erratic car chase and eventual confrontation. A private security consultant who had helped Bouée organise the spying reportedly took his own life after the incident.

Bouée is understood to have still been receiving some deferred salary payments from Credit Suisse. The bank has taken the additional step of terminating his contract, which will end any payments.

The bank launched its own investigation into Goerke’s case following media reports. It has concluded that there was no evidence that Thiam or other members of the board or executive team had any knowledge that Goerke was followed “until media reported it”.

Urs Rohner, the chairman of the board of directors at Credit Suisse, said: “The observation of Peter Goerke, which has now been confirmed, is inexcusable. It is of grave concern that the responsible individuals failed to answer truthfully about this observation during the external investigation in September 2019.

“We are aware that the observations of Iqbal Khan and Peter Goerke have damaged the reputation of our bank. With the measures that we have put in place, we are sending a clear message that the board of directors firmly rejects a culture of observation.”

The lender claimed it was lied to during the investigation into Khan’s case, saying the “individuals responsible did not respond truthfully” when asked about any other spying cases. It said there were no traces of the case in the bank’s internal systems.

Credit Suisse has since apologised to Goerke and said it will continue to cooperate closely with Switzerland’s financial regulator, Finma, which appointed an independent investigator last week to look into the spying cases.

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The lender insisted that safeguards were already in place to ensure no further spying would take place, including tougher internal policies.

However, the bank has not been able to rule out the possibility of discovering other historical spying cases and said its investigation was continuing.

Allegations of a third spying case emerged this month. Colleen Graham, another former Credit Suisse executive, has reportedly claimed she was put under surveillance in 2017 during a dispute with the bank.

“Further investigations are being conducted and Credit Suisse will continue to look into any relevant indications,” a Credit Suisse spokeswoman said.