A statement posted on the website of the Islamic State of Iraq said the operation was carried out by a "hero of Islam" and was intended to hit the "mouthpieces of the wicked and evil."
The Arabic-language news channel Al-Arabiya is one of the most popular in the Middle East but is perceived by insurgents as being pro-Western. A suicide bomber driving a minibus Monday drove through at least two checkpoints before pulling up to the front of the station's Baghdad office and blowing himself and his vehicle up.
"We take responsibility for targeting this corrupt channel, and we will not hesitate to hit any media office and chase its staffers if they insist on being a tool of war against almighty God and his prophet," the announcement said.
The massive blast blew out windows in the two-story Al-Arabiya building and left much of the interior in shambles, with doors hanging off their frames. None of the dead were employees of the network.
While violence has dissipated in Iraq, attacks like Monday's still happen with disturbing regularity.
On Thursday, a suicide bomber drove a minibus into the main gate of an Iraqi army base near Saddam Hussein's hometown, killing four soldiers and wounding 10, said police and hospital officials.
It was in the latest strike against the nation's fragile security forces as the U.S. military draws down its troops.
The 7 a.m. attack took place in the town of Shurqat as soldiers were changing their shifts, according to one witness.
Two of the four slain soldiers died after being rushed to a hospital for treatment, said Dr. Samir Issa. Ten others were also taken to the hospital in Shurqat, 155 miles northwest of Baghdad and just north of Saddam's hometown of Tikrit.
The area near Tikrit has long been a hotbed for insurgents who fought U.S. troops after Saddam was ousted in 2003.
Seven years later, insurgents are increasingly targeting Iraqi security forces, as all but 50,000 U.S. troops prepare to leave the country by the end of August. As part of a security agreement between the United States and Iraq, all American troops must leave Iraq by the end of 2011.
Also Thursday morning, a roadside bomb exploded in Fallujah, 40 miles west of Baghdad, wounding five Iraqi soldiers, a policeman said.