Two CBS News journalists were missing in the predominantly Shiite southern city of Basra, the network said Monday.

CBS said all efforts were under way to find the journalists, who were not identified by the network. It requested "that others do not speculate on the identities of those involved" until more information was available.

Iraqi police said the journalists were taken away Sunday after masked gunmen entered the Sultan Palace Hotel in central Basra. The police spoke on condition of anonymity because they were not authorized to speak to media.

"CBS News has been in touch with the families and asks that their privacy be respected," the network added in a brief statement from CBS Corp. headquarters in New York.

Basra, Iraq's second-largest city, has seen fierce fighting between rival Shiite militias as part of a power struggle in the oil-rich south.

The British military turned over responsibility for the province to Iraqis in December, but maintains forces near Basra, about 340 miles southeast of Baghdad.

In New York, the Committee to Protect Journalists said it was "deeply concerned for the safety of our colleagues, and hope they are located swiftly and able to resume their important work covering this critical story."

CPJ Executive Director Joel Simon said: "Iraq is the most dangerous country in the world for journalists and the deadliest conflict for the press in recent history. Journalists face incalculable risks in order to bring us the news about what is happening on the ground there."