Wells Fargo branches will be open for an extra hour on Saturday as the bank continues to come back from Thursday's outage that rendered most of its services useless.

The nation's fourth largest bank said that an automatic power shutdown at one of its main data center facilities triggered by a smoke condition on Thursday morning was to blame for outages of its website and mobile app. Credit and debit cards could not be used and direct deposits were not reflected in account balances.

Most of its services were available as normal on Friday as its online traffic was re-routed to back-up data centers. A lingering issue was with direct deposits not appearing in accounts, including those of Wells Fargo employees.

"Even though they were not visible, the transactions were processed normally, and customers can use their accounts with confidence. This issue has now been corrected, and all transactions are visible," the company said in a statement.

Notice posted on the door at Wells Fargo in Manchester (Dan Alexander, Townsquare Media NJ)

The other lingering issue is with its mobile and online platforms as balances still may not be updated.

There may continue to be slowness in mobile and online banking. Updated balances may still not appear for customers. Wells Fargo call centers were swamped with calls from concerned customers on Friday.

The bank, with 270 branches and 467 ATMs in New Jersey, extended branch hours by one hour on Friday and will do the same in in branches normally open on Saturday.

Wells Fargo CEO Tim Sloan issued an apology on Friday and admitted that services did not return as quickly as hoped.

"We will review the system issues in detail, and do all we can to ensure that this type of disruption doesn’t happen again," Sloan said.

The bank said any Wells Fargo would reverse and of its fees incurred because of the outage.