The departure of a third auditor for a Malaysian government investment fund is putting focus on another global company that apparently failed to raise questions about what investigators are calling a large-scale fraud.

The fund, 1Malaysia Development Bhd. or 1MDB, said Tuesday that its auditor, Deloitte Touche Tohmatsu Ltd., resigned in February. Earlier disputes over the fund’s accounts led to the firing of 1MDB’s previous auditors, KPMG and Ernst & Young, according to a Malaysian auditor general’s report last year.

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