(Farah Abdi Warsameh/AP Photo)

A United States military airstrike in Somalia on Monday targeted Ahmed Abdi Godane, the head of the militant group al Shabaab, the Pentagon confirmed today.

An assessment to determine if Godane was killed in the airstrike is ongoing. If confirmed Godane's death would be a significant jolt to the Somali militant group affiliated with al Qaeda that took credit for last year's deadly attack at a Kenyan mall that killed at least 67 civilians.

Pentagon Press Secretary Rear Admiral John Kirby told reporters at the Pentagon on Tuesday that a mix of unmanned and manned aircraft fired Hellfire missiles and laser-guided bombs at an encampment in south central Somalia where it was believed that Godane was located.

Kirby said the airstrike occurred at 11:20 a.m. EDT (6:20 p.m. local time) and was based on "actionable intelligence" that led to the targeting of the encampment and a specific vehicle at the encampment.

"This operation was a direct strike against the Al-Shabaab network, specifically the group's leader, Ahmed Abdi al-Muhammad, also known Ahmed Godane," said Kirby. "We are still assessing the results of the operation, and we'll provide additional information when and if appropriate."

Kirby said that if it is confirmed that Godane was killed in the airstrike it would be "a very significant blow to their network, to their organization, and, we believe, to their ability to continue to conduct terrorist attacks."

A senior African counter-terrorism official told ABC News that Godane was targeted during a meeting of senior al Shabaab commanders outside of the coastal city of Barawe. The official said the U.S. airstrike was carried out in conjunction with an offensive by African Union and Somali government forces operating in the area.

The Pentagon spokesman said the mission was conducted by a special operations unit that he would not identify. Presumably he was referring to Joint Special Operations Command (JSOC) which has conducted previous missions inside Somalia targeting targeted the leadership of the militant group. The military command flies armed Predator drone missions over Somalia from neighboring Djibouti.

Kirby was emphatic that no American military forces were on the ground to assist with the airstrikes. However, he did not respond directly when asked if other ground forces may have helped provide laser guidance for some of the munitions dropped on the encampment.

"All I would tell you is that we continue to work with partners in Somalia and the region but I won't get any more specific than that," said Kirby.

The U.S. did not have a regular military presence inside Somalia in the years since the deadly 1993 attack that became known as "Blackhawk Down." But earlier this year a Pentagon official confirmed that beginning in 2007 small U.S. military teams worked with Somali government forces and the African Union forces known as AMISOM. Since then the number of US military personnel has grown to about 120 as AMISOM's security needs have grown.

Since 2011 the U.S. has given over $1.5 billion to the African Union and Somali government troops fighting al Shabaab.

While the terror group remains dangerous and has launched several high-profile attacks, most notably last year's Westgate Mall attack, al Shabaab has been weakened tremendously over the last two years.

Once in control of the Somali capital of Mogadishu and most of southern and central Somalia al Shabaab now only controls the area surrounding the coastal city of Barawe which is where the US has conducted much of its recent military missions targeting the group.

Last October Navy SEALS aborted an attempt to capture a high-ranking al Shabaab official at a seaside villa in Barawe after they encountered heavy resistance.

In January a US missile strike killed a top al Shabaab commander said to be close to Godane.