Two hundred Afghan police, supported by U.S.-led coalition forces, killed 13 suspected Taliban fighters in southern Afghanistan following a spate of guerrilla-style strikes in the area over the weekend, an Afghan official said Monday.

Meanwhile, a C-130 U.S. military plane carrying U.S. Ambassador Ronald Neumann (search) suffered an engine failure as he returned from a trip upcountry to see preparations for the upcoming Sept. 18 elections. The failure was blamed on an oil leak. Emergency crews were on hand in Kabul when the plane landed safely in Kabul using its remaining three engines.

Coalition and government forces suffered no casualties in the fighting Sunday night during an ongoing military operation to flush out insurgents from mountains in southern Kandahar province, said Kandahar Gov. Asadullah Khalid.

"We have the dead bodies," Khalid said, referring to the slain Taliban (search) fighters. He said 44 other suspects were arrested and assault rifles and some ammunition were confiscated.

U.S. military spokesman Col. James Yonts confirmed that more than 40 suspected insurgents had been detained. He said some may be released after questioning.

He gave no details on casualties pending completion of the operation.

Afghan and U.S.-led coalition forces killed 12 suspected militants in raids Monday on their hide-outs in Zabul province in southern Afghanistan (search), the U.S. military said Tuesday. The rebels were allegedly plotting to use the camps as staging bases for attacks aimed at disrupting upcoming legislative elections, the military said.

More than 1,100 people have been killed in the past six months, and U.S. military commanders believe the violence may worsen ahead of the legislative elections, the next key step toward democracy after a quarter century of fighting.

The U.S. military said nine other suspected militants were detained in a two-week operation that ended Friday in the eastern province of Paktika. They included "four suspected leaders and advisers of a criminal cell," arrested with "Taliban propaganda on audio tapes," and three others linked to a bomb-making cell.

U.S. Ambassador Neumann did not rule out the possibility of rebel violence at the polls, but said it would not prevent Afghans from voting.

"It will not stop them from electing a government. It will not stop them from going forward with democracy," he said during his visit to Bamiyan in Afghanistan's central highlands.

Following his return trip, when the airplane engine failed, Neumann said the C-130 could fly safely using just two engines.

"At no time did I feel at all threatened," he said. "I even went to sleep for a while."