KABUL, Afghanistan -- A Taliban militant opened fire inside the Afghan Defense Ministry on Monday, killing two Afghan soldiers in the latest daring attack inside a government or military installation.

The Taliban said one of their agents who was also an army officer planned the attack to coincide with a visit of the French defense minister. French officials said the minister, Gerard Longuet, was not in the ministry at the time.

Despite the Taliban claim, Afghan military officials said it was not immediately clear whether the assailant -- who was wearing a vest rigged with explosives -- was an enlisted soldier or an insurgent disguised in a military uniform. The vest did not explode.

The assaults over the past four days -- first inside a police headquarters, then a base shared with American troops and now the heart of the Afghan military establishment -- signal the start of the Taliban's spring offensive after a relative lull over the frigid Afghan winter.

Afghanistan's war usually follows an annual cycle, with fighting increasing in the spring and summer as insurgents pour over the mountainous border from Pakistan. But the recent security breaches suggests that the Taliban are getting better at striking at the core of the Afghan security forces.

The ferocity of the Taliban's spring offensive will help determine whether the surge of more than 30,000 additional U.S. troops that President Barack Obama announced in December 2009 succeeded in arresting the insurgency.

The string of attacks since Friday shows that while the insurgents have suffered setbacks in their southern strongholds, they still have a slate of militants willing to take on deadly missions.

The assaults also demonstrate the geographical reach of the insurgency beyond the south. The most recent attacks were in Kabul and eastern Laghman province, while a deadly attack against the United Nations earlier this month happened in the previously peaceful northern city of Mazar-i-Sharif.

On Monday morning, a man dressed in an army uniform opened fire at the door of the Defense Ministry compound's main office building. He shot and killed one soldier at the entrance, then killed another as he bounded toward the stairs that lead to the offices of the minister and other high-ranking officials, ministry spokesman Gen. Mohammad Zahir Azimi said.

Another seven soldiers -- including two officers -- were wounded in a shootout before the attacker was killed with a shot to the head.

Taliban spokesman Zabiullah Mujahid said the attacker was an army officer who had been in the service for at least three years and was stationed at the Defense Ministry. He said he worked in concert with two accomplices. Azimi said there was only one attacker.

The Afghan Defense Ministry is well guarded, with at least three checkpoints stopping vehicles and people before they reach the main entrance. Soldiers are required to show identification to enter and visitors must be confirmed by the people they're meeting.

The attack came two days after an Afghan soldier working as a Taliban sleeper agent turned on his colleagues, killing five NATO service members, four Afghan soldiers and an interpreter. A day earlier, a suicide bomber dressed as a policeman blew himself up inside the Kandahar police headquarters complex, killing the top law enforcement officer in the restive southern province.

Insurgents have long disguised themselves in the uniforms of Afghan security forces to launch attacks. But increasingly over the past year, enlisted soldiers and police have turned on their NATO and Afghan colleagues -- sometimes because arguments have inflamed tensions or because of an alliance or sympathy with the Taliban.

The Afghans are ramping up recruitment of soldiers and policemen so they can take the lead in securing their nation by the end of 2014. They have added more than 70,000 police and soldiers last year in an effort to reach 305,000 troopers by the end of this year.

These recruits are supposed to be vetted by past employers or at least village elders. Even with those policies in place, there's often a dearth of information about those who enlist.

Azimi said that the military has tightened vetting of recruits and will continue to do so.

"Such incidents will make us focus more, and of course it will cause some changes to the procedures," he told The Associated Press.

International military advisers are working with Afghan forces to train soldiers to spot possible infiltrators.

"The insider threat is real. The expansion of the Afghan army requires that more emphasis be placed on the screening and vetting of new personnel as well as the spotting and assessing of those already in the ranks," said Lt. Col. David Simons, a spokesman for the NATO training mission.

Monday's attack also signified sophisticated Taliban intelligence gathering. Azimi confirmed that the French defense minister had been scheduled to meet with his Afghan counterpart Monday afternoon, though the information had not been publicly released for security reasons.

That meeting occurred on time and without incident inside the very building the gunman had forced his way into earlier in the day, Azimi said. Longuet also met with President Hamid Karzai later Monday, the president's office said in a statement.

Longuet arrived Sunday and had been meeting with French troops in the east. Some 3,850 French troops are deployed in Afghanistan as part of the NATO mission.

French defense officials wouldn't comment on the attack except to say Longuet wasn't there at the time. "We don't comment on Taliban declarations," French military spokesman Thierry Burkhard said.

"We are always very vigilant with the measures of precaution taken" for travels in Afghanistan, he said.

France assures its Afghan partners of its "determination to remain committed at their sides in the fight against the plague of terrorism," Foreign Ministry spokesman Bernard Valero said in an online briefing Monday.

Last week, U.S. Secretary of State Hillary Rodham Clinton warned NATO foreign ministers against bringing their own forces home too soon. The United States is worried that pressure will grow within the alliance to match U.S. withdrawals planned for July and answer rising discontent with the war in Europe.