Gunmen abducted the president of the Libyan Olympic Committee in the nation's capital, grabbing him from his car and bundling him into a waiting vehicle, his brother said Monday.

Salah al-Alam said his brother, committee chief Ahmed Nabil al-Taher al-Alam, was kidnapped on Sunday near the organization's offices in central Tripoli. He said there has been no contact with him or the captors since.

Security officials said they are investigating al-Alam's disappearance. They did not provide any further details.

Salah Al-Alam said he learned of the abduction from his brother's friend, who was with the LOC chief when the kidnapping took place. The gunmen stopped al-Alam's car, shoved him into another car and sped off, leaving the friend unharmed on the street.

The abduction comes amid a wave of score settling between rivals of Libya's eight-month civil war that ended with the capture and killing of longtime dictator Moammar Gadhafi in October. Dozens of former rebel groups now operate independently, often ignoring the nation's weak central authorities.

Since Gadhafi's fall, militias frequently have taken matters into their own hands and rounded up officials with ties to the ousted regime.

Al-Alam, who served as the head of the Libyan Football Association under Gadhafi, is known to have been friends with Gadhafi's son, Mohammed, who was al-Alam's predecessor as the Libyan Olympic Committee president.

International Olympic Committee President Jacques Rogge expressed "grave" concern about the kidnapping, and said his office has "offered any possible help if we can do something."

"Hopefully this will evolve in a good way," he told reporters in a conference call from Lausanne, Switzerland.

Five Libyans have qualified to compete in the 2012 Summer Olympics to be held in London.