(CNN) -- Seven months after he toured the United States and days after his forces were accused of gunning down 150 captive civilians who had been told they'd be freed, Khamis Gadhafi is dead, a rebel commander said.
Khamis headed the notorious 32nd Brigade, which long had been charged with protecting the Gadhafi family and had been central -- and, according to a U.S. official and human rights advocates, notorious -- in Libya's ongoing conflict.
Mahdi al-Harati -- the vice chairman of the rebel's Military Council, the military wing of the National Transitional Council -- said that Khamis was killed after a battle with rebel forces between the villages of Tarunah and Bani Walid. The battleground is in northwest Libya, near Misrata.
Khamis was taken to a hospital where he died from his injuries, said the rebel commander.
He was then buried in the area by rebel forces, according to al-Harati.
Rebel officials have made previous claims, which later appeared untrue, reporting the death or capture of members of Gadhafi's family. There has been no immediate confirmation of Khamis Gadhafi's death from officials affiliated with Moammar Gadhafi.
Khamis commanded a special forces unit, also known as the Khamis brigade.
This spring, U.S. Vice Adm. William Gortney of the Joint Staff describe the brigade as "one of the most active in terms of attacking innocent people."
Among other purported attacks, forces commanded by Khamis Gadhafi killed an estimated 150 captive civilians on August 22 as they retreated from Tripoli, alleged survivor Muneer Masoud Own told CNN.
Rebels advancing on Tripoli discovered the bodies, charred beyond recognition, in a warehouse next to a military base. In addition, a resident who lives nearby told CNN that at least 22 bodies were found in a ditch near the base, but it was not clear whether those remains were connected to the killings.
CNN cannot independently verify the claims.
Human Rights Watch and Amnesty International have detailed an incident they believe is the same one. Fred Abrahams, a special adviser for the former advocacy group, said Human Rights Watch found 45 bodies in a warehouse but added it is possible there were more deaths.
Seven months ago, Khamis was traveling across the United States and meeting with, among others, Deepak Chopra, defense contractors and U.S. military experts.
The program included contacts with AECOM Technology Corp., which had been involved since 2008 in a multibillion-dollar initiative with Libya to modernize the country's infrastructure.
It was the company's understanding Khamis was an MBA student from a university in Spain, AECOM chief communications officer Paul Gennaro said this spring.
"We were aware of the student's family relationship, but we were not informed of any military connection whatsoever," Gennaro said, adding AECOM was "shocked and outraged" to learn of the young Libyan's role in his country's crisis.
U.S. Air Force Academy spokesman John Van Winkle told CNN that while Khamis Gadhafi was in the United States, he was given a "standard tour" of the Colorado Springs, Colorado, campus on February 7.
Khamis also flew to Chicago for training with AECOM lawyers on such topics as "global contract management" and "foreign corrupt practices training."
It was in Illinois, in a session on leadership, that he met Chopra. The wellness guru described Khamis as impeccably dressed in a hunting jacket, polite and unassuming. Chopra said Gadhafi said he was "in the investment business."
"We had been informed by the State Department that he was going to be there, that he didn't want to use his official name and we should respect that," Chopra told CNN by phone earlier this year. "So he introduced himself with his name, but he didn't use the name Gadhafi."
But in March, U.S. State Department spokesman Mark Toner denied the department had approved any meetings that involved Khamis Gadhafi, calling it a "private internship" that did not require department approval.
Khamis Gadhafi next went to Washington, where he met with -- among others -- representatives from defense contractor Northrop Grumman. A spokesman for the company, Randy Belote, confirmed such a meeting took place.
National War College spokesman Dave Thomas said the son of Gadhafi visited there, accompanied by a State Department representative, and met with faculty and deans. Tactics were not discussed, though the "structure of military education" was, Thomas said.
New York Stock Exchange spokesman Richard Adamonis also confirmed that Khamis Gadhafi visited the exchange as part of a group on February 17.
But later that day, he cut short his tour to return to Libya.
By March, Khamis Ghadafi was being featured on Libya's state TV, which aired footage from the family's Tripoli compound showing him dressed in uniform and greeting people.
CNN's Salma Abdelaziz, Tom Watkins, Pam Benson and Brian Todd contributed to this report.