Credit Suisse's operating boss is leaving after an investigation found he was behind a private surveillance scheme on Iqbal Khan, a departing executive of the Swiss bank. CEO Tidjane Thiam wasn't in the loop.

The Zurich-based's operating chief Pierre-Olivier Bouee (pictured below) is leaving with immediate effect, and will be replaced with a James Walker, a finance executive, it said in a statement on Tuesday. 

Pierre Bouee 500

The exit of the Frenchman as well as the Swiss bank's head of global security is the culmination of a ten days of damaging fallout over a run-in near Zurich's tony Paradeplatz square. Ex-Credit Suisse top banker Iqbal Khan confronted a private detective tailing him. The messy episode turned tragic: a middleman between the Swiss bank and the detective died by suicide, according to multiple reports citing his lawyer.

«Wrong and Disproportionate»

Credit Suisse's admission of its role in the «spy» scandal comes on literally the same day that Khan start at crosstown rival UBS. The 43-year-old will co-run the Swiss bank's flagship wealth management arm, and is widely tipped as the most promising internal candidate to succeed UBS' 59-year-old CEO Sergio Ermotti.

Credit Suisse said an outside investigation found that Bouee ordered Khan followed by a private detective as soon as the banker's move to UBS was made public in August. «The board of directors considers that the mandate for the observation of Iqbal Khan was wrong and disproportionate and has resulted in severe reputational damage to the bank,» Credit Suisse said.

CEO Not Informed

Bouee, a long-time associate of CEO Tidjane Thiam, didn't tell his boss, nor the board of the scheme, Credit Suisse said the investigation found. Neither the bumbled security operation nor the shadowing of Khan turned up any evidence the wealth manager was busy trying to line up employees or clients to poach to UBS, Credit Suisse said.