Hundreds of insurgents attacked Afghan police checkpoints in a remote northeastern province Tuesday with AK-47s and rocket-propelled grenades but failed to overrun the government positions, officials said.

The assault in Nuristan, a rugged and mountainous area province Pakistan, is the second significant Taliban attack on Afghan government forces in less than four days and is part of the insurgents' long-awaited spring offensive.

The effectiveness of the Taliban's campaign could affect the size of President Barack Obama's planned drawdown of U.S. troops in July, the scale of which military officials have said will depend on conditions on the ground.

Nuristan province police chief, Gen. Shams-ul Rahman Zahid, said about 400 Taliban fighters launched their assault at dawn, striking government security outposts around a base housing reserve police units some 11 miles (18 kilometers) south of the provincial capital of Parun.

The gunbattles tapered off just before nightfall with the police still in control of the four checkpoints, which had been reinforced by more police from Parun, he said.

Zahid declined to say how many police had come under attack or the size of the security force based in Nuristan, although it is thought to be small. He acknowledged asking NATO and the Afghan army for help.

Taliban spokesman Zabiullah Mujahid claimed responsibility for the attack.

In Kabul, the Afghan military said it would not send reinforcements, while NATO claimed to know nothing about the attacks. There are few coalition or Afghan Army troops in mountainous Nuristan, near the Pakistan border.

Defense Ministry spokesman Gen. Mohammad Zahir Azimi said the army was aware that "hundreds of insurgents" had attacked police forces in Nuristan but had no immediate plans to dispatch troops to the area. He said he did not have further details because there are no army forces in the area.

Asked why he wasn't dispatching troops, Azimi said that at this point the police were still holding their ground. He said the Afghan army does not have troops stationed in Nuristan because it doesn't have the personnel available to cover the remote area.

The American commander in charge of the area disputed the number of Taliban attacking but said the U.S. sent an unmanned drone to the area to check on the situation.

Speaking from Bagram Air Base, Maj. Gen. John Campbell told a Pentagon press conference that in the year he has been there, "we have never seen ... 400 insurgents mass."

The Taliban launched the first major strike in its spring campaign over the weekend in the city of Kandahar, the movement's birthplace and the economic hub of southern Afghanistan, hitting government buildings across the city in a full frontal assault. At least two dozen insurgents, two members of the Afghan security forces and one civilian were killed in two days of fighting in the city.

The Taliban and other insurgent groups control large swaths of Nuristan, Kunar and other northeastern provinces near the Pakistani border. Insurgents retain safe havens in Pakistan's neighboring lawless tribal regions and cross the border into Afghanistan to attack NATO troops.

Hizb-i-Islami, a militant group made up of loyalists of regional warlord Gulbuddin Hekmatyar, also has a large presence in the region. They are not thought to be taking part in the attacks. The area also has smaller ultraconservative Salafi groups.

Zahid said he had intelligence that the strikes were being carried out by Pakistanis and Arabs who have been crossing the border into Afghanistan.

The Taliban also control the tiny capital of Nuristan's rugged Waygal district, which they overran with more than 300 fighters on March 29 and raised the white flag of the Islamic Emirate of Afghanistan — as the country was known when it was under Taliban control before the 2001 U.S. invasion. Zahid said they also directly control half of Kamdesh district.

"Unfortunately Waygal is still under control of the Taliban. We are waiting for the Ministry of Interior to instruct us. We have not acted to take it back after it collapsed," he said

Violence also continued in other parts of Afghanistan. NATO said Tuesday that three of its service members were killed by roadside bombs, one on Tuesday in the east and two on Monday in the south. France confirmed one of the soldiers was French, and the other two were Romanians, their government said. Seven NATO troops have died this month, and 158 have been killed since the start of the year.

In southern Zabul province, the Afghan Ministry of Defense said one of its commando units killed five insurgents, including two Pakistanis. It also said two armed foreign nationals, a Frenchman and a Moroccan, were detained "along with ammunition, weapons, military equipment and propaganda letters."

It provided no further details on the two foreigners.

In eastern Paktika, the provincial governor's office said six insurgents were killed and another eight captured in Afghan police operation.