Wells Fargo has been investigating internal complaints of gender bias in its wealth management division for months and is looking into at least one formal human resources complaint about the division's head, a man, according to a report in The Wall Street Journal on Friday.

Female executives at Wells Fargo have raised concerns about gender bias in the bank's wealth management division, the Journal reported. A dozen women who are executives in the division met in Scottsdale, Arizona, in June to discuss the concerns, particularly the lack of women in senior roles.

The Journal talked to six women who are Wells Fargo executives who either attended the meeting or had direct knowledge of it.

They told the Journal that qualified women recently had been turned down for top jobs that went to men, and when women did raise concerns they felt ignored.

They also said part of the internal investigation focuses on a complaint against Jay Welker, president of Wells Fargo's private bank and head of the wealth-management division since 2003, who reportedly told some executives that "women should be at home taking care of their children." Some of the women told the Journal he often called women "girls" or told them to put their "big girl panties on."

A spokeswoman for the bank said in response to a request by CNBC for comment, "On his behalf, Jay doesn't have any comments on this."

The spokeswoman separately told CNBC in an email, "We value all of our Wells Fargo team members, and we take seriously any allegation raised by a team member, or against a team member. We ensure that concerns raised are thoroughly and objectively investigated, while taking measures to protect confidentiality. Once an investigation is complete we are committed to taking any appropriate action. At Wells Fargo we are committed to promoting diversity and inclusion in all aspects of our business, which we believe is essential to engaging our team members, customers, communities and shareholders."

Wells Fargo has fewer females in top leadership roles compared with its wealth-management peers on Wall Street, the Journal reported.

The country's third-largest bank has dealt with multiple scandals across its major business units in the past two years. In 2016, it was revealed that branch employees had opened millions of fake accounts in customers' names without their knowledge to meet sales targets.

Wells Fargo switched up its executive ranks following the scandal but other investigations into its sales practices unearthed issues in its auto lending, mortgage and wealth management.

Earlier this year, Wells Fargo agreed to pay a $1 billion fine over misconduct in its mortgage lending and auto businesses. In February, the Federal Reserve restricted Wells Fargo's loan growth until it makes several internal changes to its risk management. In April, the Journal reported that financial advisors pushed clients into products or investing platforms meant to generate more revenue for the bank than returns for customers, which the Justice Department and SEC are investigating.

— Read the entire Wall Street Journal report here.