WASHINGTON (CNN) -- The attorney general and the FBI director have asked the nation's leading Internet service companies to keep a variety of customer information and other data for two years, much longer than the companies do now, the Justice Department confirmed Tuesday.

Companies have varying policies regarding what information is kept and for how long.

One thing the Justice Department wants is some type of subscriber information, such as the Internet address assigned to a person when logging on to a service provider, according to two sources familiar with a meeting that was held last week between the government and the Internet companies.

The online industry is expected to strongly oppose any request to retain these types of records because of privacy concerns for their customers.

"It is a slippery slope," one of the sources said of the government's interest in the information. "It becomes a fishing expedition."

The Internet companies have said there are other ways to get the information without them having to hand it over and believe requests like this are burden to the industry, the sources said.

Justice Department spokesman Brian Roehrkasse said government and private industry officials are continuing to discuss the privacy issues involved and some of the concerns raised by the companies at the meeting Friday at the Justice Department.

The meeting, first reported by CNET News.com, included representatives from Verizon, Comcast, AOL (which is owned by Time Warner, as is CNN.com), Microsoft, Google and the U.S. Internet Service Provider Association, the sources told CNN. Companies involved refused to comment on the meeting.

The original request for the record retention came as part of the Justice Department's efforts to fight child pornography. During a speech last month, Attorney General Alberto Gonzales said he would press the CEOs of Internet service providers about retaining records.

During last week's meeting, though, the FBI "made clear they wanted [information on subscribers] for other reasons as well. ... Terrorism was mentioned," one of the sources said.

After the September 11, 2001, terrorist attacks President Bush authorized the National Security Agency to secretly monitoring e-mail and phone calls to track people linked to terrorist activity.

Earlier this month USA Today reported three telecommunications giants provided the NSA, the nation's super secret spy agency, with records from billions of domestic phone calls after 9/11.

Another meeting of government and industry representatives is scheduled for Friday, according to an official of the Internet Service Provider Association.