NEW YORK (AP) — Chase's online banking service was down for much of the day on Tuesday. The bank said it stemmed from a technical problem and that it was working to resolve it.

The service went down Monday night, potentially affecting its 16.5 million customers who bank online. Chase spokesman Thomas Kelly couldn't specify the exact time service was disrupted.

The bank will work with any customers who had online bill payment deadlines they couldn't meet because of the outage, Kelly said. He also urged Chase customers to use the telephone banking service, which was operating normally, as were its 15,500 ATMs.

Online bankers who logged on to its website Tuesday, www.chase.com, were met with a note that said: "Our website is temporarily unavailable. We're working quickly to restore access. Please log on later.

Chase bank is part of JPMorgan Chase & Co.