The two heads of Credit Suisse’s prime brokerage business are to leave just weeks after the bank reported at least $4.7bn of losses related to the family office Archegos Capital.

John Dabbs and Ryan Nelson have stepped down from leading the unit, which offers specialised services to hedge funds, according to a staff memo seen by the Financial Times.

They are the latest in growing list of senior and mid-level executive departures as the bank reels from twin crises involving Archegos Capital and supply-chain finance company Greensill Capital.

The Swiss lender has previously announced the departures of Brian Chin, its head of investment banking, and Lara Warner, its chief risk and compliance officer.

Credit Suisse was one of several global banks hit when their client, Archegos — a family office run by former hedge fund manager Bill Hwang — unravelled last month. Some banks including Goldman Sachs escaped relatively unscathed, while Credit Suisse nursed its heaviest trading losses for at least a decade.

The memo announcing the new departures was sent on Monday by Anthony Abenante, who took over temporarily as head of equities sales and trading this month. Dabbs, who is based in New York, and Nelson, who is based in London, will step down immediately but assist the team to ensure an orderly transition until mid-May, it said. The departures were first reported by the Wall Street Journal.

Abenante added that Roger Anerella had been appointed interim head of prime services, while, Doug Crofton was named head of Americas cash and Stuart McGuire filled a similar role in Europe.

Credit Suisse is due to publish its first-quarter results on April 22 and has already indicated it will report a $960m loss because of the Archegos debacle. The FT last week reported staff bonuses have been cut by hundreds of millions of dollars.

The Archegos losses followed the suspension last month of supply-chain finance funds linked to Greensill that Credit Suisse offered to its clients. The Swiss bank has calculated its clients could lose up to $3bn from the funds, which the bank froze at the start of March.

Both episodes have raised questions over the risk management processes within the bank.

Christian Meissner, Credit Suisse’s co-head of international wealth management investment banking advisory, will replace Chin on May 1. Warner, who left on April 6, was replaced by Joachim Oechslin as interim chief risk officer and Thomas Grotzer as interim global head of compliance.