The die-hard Taliban militants in the latest string of dreadful attack stormed the largest U.S. military base in Afghanistan - Bagram airfield - 50 km north of Kabul Wednesday morning, wounding at least five foreign service members.

Engagement between the two sides, said a statement issued by the NATO-led International Security Assistance Force (ISAF), left seven attackers dead and five troopers injured.

The shocking attack on the well-guarded base which took many into surprise was the second of its kind over the past two days.

The previous offensive in the shape of suicide car bombing against the NATO-led troops in Kabul left 18 people dead including five Americans and one Canadian soldiers.

Taliban militants, challenging the Afghan and NATO-led troops, in contact with media via telephone from their hideouts have claimed responsibility for both attacks.

In Wednesday's attack, according to the Taliban purported spokesman Zabihullah Mujahid, 42 foreign soldiers had been killed and several others sustained injuries, a claim rejected by the U.S. military as groundless.

"Seven insurgents have been killed during engagement on Bagram. Five service members were wounded and a building received minor damage," said the ISAF statement.

"We are always prepared to deal with attacks on our base, the response this morning was immediate," Lt. Col. Clarence Counts, a spokesman of the U.S. army at the Bagram base, was quoted as saying.

Meanwhile, Taliban spokesman Zabihullah Mujahid, in talks with media from an unknown location, described it a successful attack, stressing 42 foreign soldiers have been killed at the base and several others sustained injuries.

He also said that the 20 militants equipped with suicide vests infiltrated the Bagram airfield at 05:00 local time and four of them blew themselves up causing casualties on the troops.

However, Afghan Interior Ministry spokesman Zamarai Bashari said in talks with Xinhua that the situation in Bagram has been brought under control.

Taliban-linked militancy has been on constant rise since this spring.

The militants who largely rely on suicide attacks and roadside bombings announced in a statement earlier this month to kick off a spring offensive from May 10.

The legitimate targets of the offensive, according to the statement, are Afghan military and NATO-led multinational peacekeeping force (ISAF), foreign diplomats and anyone serving the Afghan and U.S.-led Coalition.

More than 200 NATO-led troops, with the majority of them Americans, have been killed since the beginning of this year in Afghanistan, almost double the number of NATO-led forces casualties against the same period in 2009.

Military experts including Afghan and NATO-led forces commanders have predicted more violence in the current year in the militancy-plagued central Asian state.