Warplanes carried out multiple bombing raids in the northern Iraqi city of Mosul on Sunday, a day after the leader of a powerful al-Qaeda-inspired militant group appeared online in a video from the city’s main mosque.

Residents of the city, reached by phone, said airstrikes shook the city at least three times Sunday, starting at dawn. It remains unclear what force carried out the airstrikes. The U.S. Defense Department said that it had no knowledge of the airstrikes and that U.S. forces were not involved. An Iraqi government official in Baghdad said he had no information about any airstrikes near Mosul.

On Friday, Abu Bakr al-Baghdadi, the leader of the Islamic State, which declared a revival of the medieval Islamic caliphate in Iraq and Syria last week, delivered a sermon to worshipers from Mosul’s Great Mosque.

The video, which appeared online Saturday, marked the first time that the elusive extremist leader has appeared in a video.

The fact that Baghdadi ventured into public at all appeared to underscore just how solidly the group controls Mosul, which it seized June 9 in a stunning offensive that simultaneously instigated the collapse of an entire regional division of the Iraqi army.

At least one of the strikes on Sunday tore through a cluster of homes in the village of Rashidiya, on Mosul’s northern outskirts, one local resident claimed, charging that the dead were civilians.

“There were four houses destroyed. Two families were killed,” said a 75-year-old retired military officer who lives in the area.

Hamid al-Mutlaq, a Sunni member of parliament who until recently served on the security and defense committee, confirmed that airstrikes had destroyed a number of homes in Rashidiya and in the Mosul neighborhood of Tamooz. A local medical official told the Associated Press that at least seven people were killed in the strikes and 30 were wounded.

A pro-government news Web site said dozens of Sunni militants from the Islamic State were killed in an airstrike on a presidential palace compound in north Mosul.

A former air force pilot who spoke from the city center Sunday said that the strikes marked the first in days but that he wasn’t sure of the targets.

“The doors and windows have been shaking,” he said over the phone. The man requested anonymity for fear of retribution.

An official in the office of Iraqi Prime Minister Nouri al-Maliki said that he had no information about airstrikes in or around Mosul. The Iraqi military could not be reached for comment.

An Iraqi man called on Baghdad to "have some shame" after his 12-year-old relative was killed by a government air strike in Tuz Khurmato on Monday. (Reuters)

But the former pilot described seeing an American-made C-130 military transport plane that could belong to the Iraqi air force. “It’s a cargo airplane. Not a drone,” he said. Over the past seven days, the residents had heard the sound of drones, he said. This was different.

Other residents said they couldn’t see the planes because the aircraft were flying high but that they heard the noise of the strikes. Some, including Mutlaq, the parliamentarian, blamed Iran.

On Saturday, Iranian state media reported that an Iranian pilot had been killed in Iraq. Iran’s official Islamic Republic News Agency did not publish details of how the man died but said that he was killed defending the Shiite holy city of Samarra, which lies near the edge of the Islamic State’s control, north of Baghdad.

The Iraqi military says it carried out a series of airstrikes in recent weeks on areas now controlled by Sunni militants, particularly in the city of Tikrit, former dictator Saddam Hussein’s home town.

There have been no confirmed U.S. drone strikes or Iranian airstrikes in Iraq.

But the United States is currently flying armed and unarmed drones over Iraq, U.S. officials have said.

Washington has dramatically increased its aerial surveillance of the country over the past month since militants from the Islamic State in Iraq and Syria, now known as the Islamic State, swept control of a vast swath of territory stretching from eastern Syria into central Iraq.

Mosul residents said that local communication networks shut down Friday and were not functioning midday, when Baghdadi would have arrived at Mosul’s Great Mosque to deliver his sermon.

“We thought Baghdad had blocked it to isolate us from the world,” the former pilot said, referring to the Iraqi central government, which has vowed to recapture Mosul from the militants. Now he said he believed that the Islamic State had blocked it to shield Baghdadi’s movements that day.

It’s unclear if the Iraqi government or Washington was aware of Baghdadi’s whereabouts before the appearance of the video Saturday.

In 2011, the United States named Baghdadi a specially designated global terrorist and offered a $10 million reward for information that could lead to his capture.

On Sunday, a spokesman for Iraq’s military told reporters that Iraqi forces were studying the video and had yet to reach a conclusion on whether the man in it was, indeed, Baghdadi. But the SITE Intelligence Group, which closely monitors extremist groups in the region, confirmed that it was Baghdadi.

Khalid Ali in Baghdad and

Karen DeYoung in Washington contributed to this report.