KABUL, Afghanistan — Al-Qaida is present along the border region of Pakistan and Afghanistan and is encouraging Afghan insurgents to disrupt presidential elections scheduled in just two weeks, on Oct. 9, the commander of U.S. forces in Afghanistan, Lt. Gen. David Barno, said Saturday.

"We see indications that al-Qaida is encouraging a disruption of elections," Barno said.

He added that the military has detected an al-Qaida presence in the southeastern provinces of Khost, Paktia and Paktika, across the border from Pakistan's region of South Waziristan where the Pakistani army has been engaged in heavy fighting with foreign militants.

Al-Qaida allies, including supporters of the Taliban and the former mujahedeen leader Gulbuddin Hekmatyar, who have voiced their opposition to the U.S.-backed presidential elections, were planning to increase attacks in Afghanistan, Barn said.

"Terrorist attacks will continue and more than likely increase as the election nears," he said.

The insurgents have only a couple of thousand men, he said, a tiny minority compared with the 10.5 million people who have registered to vote. Yet the border with Pakistan is long and porous and infiltration by militants across the border will be a long-term problem, he said.

The 17,000 U.S. troops in Afghanistan and 9,500 NATO peacekeepers would have to show strong resolve to support the Afghans over the coming weeks, the general said.

Signs have suggested an increase in Taliban activity in southern Afghanistan in the last week.

As many as 15 police officers were killed in three simultaneous attacks overnight on Friday on police stations on the main road in Helmand province, a local commander, Hajji Mir Wali, said. The attackers were suspected of being Taliban, he said.

Three U.S. soldiers were killed and a number of Afghan and U.S. soldiers wounded Monday in several clashes with militants, the U.S. military said this week.