(CNN) -- Verizon Wireless has fired employees connected to a breach of records from a cell phone used by President-elect Barack Obama this year, a Verizon source said Friday.

An Obama spokesman said Verizon Wireless workers looked through an old phone's billing records.

The source would not say how many people were terminated but said "we now consider this matter closed."

Verizon reported the breach Thursday, and Obama spokesman Robert Gibbs said the transition team had been notified Wednesday. Gibbs said the president-elect no longer uses that phone, which has been inactive for months.

The fired employees were hired "to take care of customers," the Verizon source said, and were not authorized to access customer records unless asked to do so by the customer.

The source also said the employees in question could not have read text messages, if Obama sent or received them, and would not have been able to access the content of any voice mail messages, although they would have been able to see whether any had been left.

"This was some employees' idle curiosity," the source said, adding that records of no other customers of note were breached.

Ari Schwartz of the Center for Democracy and Technology said the employees probably had access to the dates and times of calls, the length of calls and the telephone numbers of those Obama spoke with.

Verizon CEO Lowell McAdam said Thursday that the company initially put all employees who had access to the account, "whether authorized or not," on leave during an investigation.

McAdam said the device on the account was a simple voice flip-phone, not a BlackBerry or other smartphone designed for e-mail or other data services, meaning none of Obama's e-mail could have been accessed.

Verizon Wireless, meanwhile, has launched a separate internal investigation to determine whether Obama's information was shared only among employees or whether "the information of our customer had in any way been compromised outside our company, and this investigation continues," McAdam said in an internal e-mail obtained by CNN.

The company has alerted "the appropriate federal law enforcement authorities," McAdam said.

CNN's Brian Todd and Ed Henry contributed to this report

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