(Bloomberg) -- A failed oil trader in Singapore that owes creditors more than $3.5 billion is suing Deloitte & Touche LLP, alleging the auditing firm failed to detect “serious irregularities” in its financial statements for more than a decade.Deloitte audited the books of Hin Leong Trading Ltd. for at least 16 years before the firm collapsed last year when founding tycoon Lim Oon Kuin admitted trading losses of $808 million weren’t reflected in the firm’s financial statements, according to a cou