More than 16 tons of drugs — mostly opium — were also seized in Bahramcha district of Helmand province, center of a Taleban-led insurgency and Afghanistan’s biggest poppy-growing region, the Interior Ministry said.

“Sixty-three terrorists were killed,” the ministry said in a statement, referring to Taleban-linked insurgents. “The operation was successfully completed,” the statement said.

Two factories for converting opium into heroin were destroyed and “a large number” of weapons and ammunition were also seized in the raids, begun Friday by Afghan counternarcotics commandos supported by NATO troops, it added. The commandos also freed 10 villagers captured by rebels for allegedly working with the government while arresting 10 rebels and drugs traffickers, the statement said.

Meanwhile, US Gen. David Petraeus said the nine-year war in Afghanistan has reached a critical stage.

“We are engaged in a tough fight. After years of war we have arrived at a critical moment,” Petraeus told guests at a change-of-command ceremony at the NATO-led International Security Assistance Force (ISAF) headquarters in Kabul.

“We all recognize the threat that the Taleban, Al-Qaeda and the other associated syndicate of extremists pose to this country, this region and to the world,” he said. “We are in this to win.”

Petraeus, wearing camouflage fatigues and speaking near a marble column dedicated to ISAF troops killed in the Afghan campaign, told senior commanders and several Afghan ministers his appointment signaled a change in command, not strategy.

Despite last month being the bloodiest yet for international troops, he said gains were being made in the increasingly difficult war and a pushback by insurgents had been expected ahead of an offensive by US and NATO troops on Taleban strongholds in the country’s south.

“Nothing has been easy in Afghanistan,” he said. “However, we can all take heart from the progress that has been made on the security front and beyond.”

Petraeus has just months to show progress in turning back an emboldened enemy and convince both the Afghan people and neighboring countries that the US is committed to preventing Afghanistan from again becoming a haven for Al-Qaeda and its terrorist allies. Continual discussion about President Barack Obama’s desire to start withdrawing US forces in July 2011 has blurred the definition of what would constitute victory. That coupled with the abrupt firing of Petraeus’ predecessor, a move that laid bare a rift between civilian and military efforts in the country, has created at least the perception that the NATO mission needs to be righted.

As he accepted the command, Petraeus took a stab at clarifying the goals.

“We are engaged in a contest of wills,” he told several hundred US, coalition and Afghan officials who gathered on a grassy area outside NATO headquarters in Kabul. By killing and maiming civilians — even using “unwitting children to carry out attacks” — the Taleban and their allies are trying to undermine public confidence in the Afghan government and the international community’s ability to prevail, he said.