Computer files with confidential data on about 5,000 employees at MTV Networks were breached by someone outside the company, the network told employees on Friday in a memo.
MTV later said in a statement that the security breach occurred after an Internet connection in an employee's computer was compromised.
Although it was not immediately clear whether the password-protected files were opened, MTV, a division of Viacom, notified law enforcement authorities and a credit monitoring company to safeguard the identities of the affected employees, the statement said.
The company declined to provide any information about how many employees were affected or the nature of the compromised information.
The internal memo, from Catherine Houser, executive vice president for human resources at MTV Networks, said the personal information in the files included names, birth dates, Social Security numbers and compensation data.
The company encouraged the affected employees to place a 90-day fraud alert on their credit files with the three major credit agencies, and offered credit monitoring for two years at company expense.