YEKATERINBURG, Russia - A high-ranking Russian diplomat admitted Wednesday that countering Al-Qaeda has become more complicated after its leader, Osama Bin Laden, was killed.

According to Ilia Rogachov, director of the Department for New Challenges and Threats in the Russian Foreign Ministry, Bin Laden's death has destroyed the terror group's vertical structure.

"Al-Qaeda is different now with no central command, no links between its cells. This is modern terrorism which went in-depth. Countering it has been much more difficult than 10 years ago," Rogachov told the second international security conference here.

He added that the situation in Central Asia has been "worrisome," with Afghanistan as a key source of instability.

Rogachov also rebuked operations of NATO-led forces in Afghanistan for concentrating their efforts in the south and the east of the country, which led Taliban's forces to relocate to the north, closer to Central Asia.

"We have some questions to our partners on the international security forces in Afghanistan," the diplomat said.