A large German bank has come under fire for creating psychological profiles of more than a million of its customers, German media report.

Customers of Haspa, a division of Sparkasse, were labeled as "adventurers," "conservationists," "hedonists" and other categories based on interactions with bank personnel, German public broadcaster NDR reported.

Bank financial advisers were trained in how to persuade each personality type to invest in financial products, NDR reported.

For example, the "adventurer" is "motivated by risk, conquest and struggle," so "arguments should be strongly emotional, to trigger their sense of impulsive decision making," NDR reported.

"Hamburger Sparkasse are doing the opposite of helping their customers make responsible choices, by getting into their heads to manipulate them into make choices that are not really in their interest," consumer advocate Edda Castello told NDR.

The bank said it would halt the practice, German news service The Local reported.