CNN reported that two suspects have been arrested in Mosul, according to Gen. Jalal Tawfeeq, military operations commander of Nineveh province, who spoke to al-Sharqiya. According to Reuters, Brig.-Gen. Khalid Abdul Sattar, the spokesman for Iraqi military operations in Mosul and Nineveh province, said police had arrested five suspects.

Musab Mahmood al-Ezawi, a senior correspondent with al-Sharqiya, cameramen Ahmed Salim and Ihab Mu'd, and their driver, Qaydar Sulaiman, were filming a show in al-Zanjali district, in Mosul, when they were kidnapped by militants, al-Sharqiya said in a statement. Their bodies were later found in al-Borsa district, a short distance from the site of the kidnapping, a local journalist told CPJ. The journalist said that all the victims were in their twenties.

On Sunday, Iraqi Prime Minister Nuri al-Maliki ordered the police in Mosul to launch an investigation, according to a statement posted on the Iraqi Prime Minister's Office Web site.

"Iraq is not only the most deadly country in the world for the press, it also has an unblemished record of impunity for the killer of journalists," CPJ Executive Director Joel Simon said. "These two facts are not unrelated. The only way to ensure a safer reporting environment for journalists is to go after those who murder them. We urge the Iraqi authorities to ensure that this investigation is timely and transparent and ensure that those who are responsible for the killings are brought to justice."

The nine-member crew was filming a family for a show called "Your Iftar Is On Us." Iftar is the meal that breaks the Ramadan fast. Each day on the show, the crew would make dinner for a poor family, and give them $2,000 and household goods.

While five crewmembers were in the house filming, the four outside were kidnapped and taken to Arbil, about 62 miles (100 kilometers) east of Mosul, the same day and killed, according to a local journalist.

At least 20 other journalists have been killed in the northern city of Mosul, 230 miles (370 kilometers) north of Baghdad since March 2003, according to CPJ research, making it the second-deadliest city in Iraq after Baghdad.

Iraq topped CPJ's Impunity Index for 2007. No one has ever been convicted for the murder of a journalist in Iraq, according to CPJ records. The death of the three al-Sharqiya journalists raised the number of journalists killed in Iraq since the U.S. led-invasion of Iraq in March 2003 to135, according to CPJ research. The murder of the driver raised the number of media workers killed in Iraq to 51. The vast majority of those killed have been Iraqis.