Deutsche Bank's net profit rose in the second quarter, but legal expenses stemming from investigations of the bank's past conduct also increased and the bank's new co-CEO said its financial performance was unsatisfactory.

John Cryan said Thursday that Deutsche Bank needed to cut costs, shed unprofitable activities and improve "poor overall returns to shareholders."

Net income increased to 818 million euros ($899 million) in the April-June quarter from 238 million euros in the same quarter last year. Taxes fell and profits rose from trading stocks in volatile markets.

Litigation expenses were up, to 1.2 billion euros from 470 million euros. The bank paid $2.5 billion in the first quarter to settle allegations it manipulated a key interest rate benchmark, and faces other probes.