Fierce fighting broke out around Afghanistan on Friday, with battles in three separate regions killing more than 100 militants, part of a cycle of rapidly rising violence five years into the U.S.-led effort to defeat the Taliban.

The governor of northeastern Kunar province said villagers were claiming that airstrikes had killed dozens of civilians, though he said he could not confirm the report.

The fighting -- in the south, west and northeast -- continues a trend of sharply rising bloodshed the last five weeks, among the deadliest periods here since the 2001 U.S.-led invasion

More than 1,000 people were killed in insurgency-related violence in June alone, including 700 militants and 200 civilians. More than 3,100 people have been killed in Afghanistan this year, according to an Associated Press count based on information from Western and Afghan officials. Around 4,000 people died in violence last year.

U.S.-led coalition and NATO spokesmen on Friday emphasized that ground commanders had evaluated the terrain to prevent civilians casualties, though Kunar Gov. Shalizai Dedar said villagers had reported that 10 civilians were killed in an initial airstrike, and that a second strike killed about 30 people who were trying to bury the dead.

Dedar said he could not confirm the reports of civilian deaths but that he was not rejecting their validity either. He said around 60 militants died in the battle.

U.S. and NATO officials say that Taliban militants threaten villagers into claiming that attacks killed civilians.

"There were some number of insurgents that were killed. We have no reason to believe that any civilians were killed at this time," said NATO spokesman Maj. John Thomas. He said soldiers called in airstrikes on "positively identified enemy firing positions" in a remote area.

Civilian deaths has been a growing problem for international forces here, threatening to derail support for the Western mission. President Hamid Karzai has repeatedly implored forces to take care to prevent such deaths.

Both a U.N. and the AP count of civilian deaths this year show that U.S. and NATO forces have caused more civilian deaths this year than Taliban fighters have.

In the south, militants attacked two police vehicles with gunfire and rocket propelled grenades overnight, and U.S.-led coalition and Afghan forces responded with artillery fire and airstrikes in what the coalition described as a "sparsely populated area" in Uruzgan province.

Gen. Zahir Azimi said 33 Taliban fighters were killed. The coalition reported "no indications" of civilian casualties and said no coalition or Afghan forces were killed or wounded.

In Farah, a western province bordering Iran that has seen little violence until this year, insurgents attacked an Afghan security patrol from fortified positions, wounding five Afghan soldiers, the coalition said.

Afghan and coalition forces, using gunfire and airstrikes, killed "over 30" insurgents, it said. The coalition also said a ground commander "carefully evaluated risk of collateral damage" before firing.

"It is important to note that many targets were not bombed or fired on due to (Afghan) and coalition force precautions against causing collateral damage," said Maj. Chris Belcher, a coalition spokesman.

In the country's east, two NATO soldiers died and several others were wounded during an operation Thursday, the alliance said.

The alliance did not release the soldiers' nationalities or the location where the clash and the bombing took place. Most foreign troops in the east are American.

The latest NATO casualties raised the number of foreign soldiers killed this year to at least 105.