'Pakistan militants plotted Karzai ambush'

KABUL, Afghanistan (CNN) -- A soldier from NATO's International Security Assistance force was killed in an explosion in eastern Afghanistan Wednesday, ISAF has said, as Afghan security forces continued their hunt for those behind the recent assassination attempt on President Hamid Karzai.

Afghanistan's intelligence chief Amrullah Saleh blamed militants from Pakistan for Sunday's incident, saying it was unclear if Pakistan's special agencies gave the "go ahead" for attack, which killed three people but left Karzai unscathed.

"The evidence once again shows that the soil of Pakistan has been used against us," Saleh told CNN. "Clearly there (is) very, very strong evidence suggesting that Pakistan soil once again has been used to inflict pain upon our nation."

Afghan security forces searching for militants tied to the attack raided several homes early Wednesday, resulting in the deaths of seven people -- including a woman and child with ties to militants -- according to Saleh.

Authorities launched the raids after interrogating a government official following Sunday's assassination attempt on Karzai, added Saleh.

The government official confessed to playing a part in the attack on a military ceremony -- which left three dead --- and pointed authorities to the three locations, Saleh said.

In the first house, east of Kabul, authorities arrested six militants. Watch the attack unfold »

In the second raid -- at a house in western Kabul -- security forces exchanged fire with militants inside.

The gunfire killed three intelligence agents trying to enter the house, Saleh said. In response, security forces blew up the residence. Two men, a woman and a child were killed in the explosion

One of the men provided the weapons for Sunday's attack, while the second drew up the plot, Saleh said.

The woman, who was not Afghan, was at the house preparing to carry out a future suicide attack, he said. Authorities suspect that the militants may have been readying the child to also carry out an attack, he added.

Saleh described the house as having a "sophisticated" setup, adding that its basement held a cache of weapons.

A raid at a third house, southeast of Kabul, was still ongoing at 4 p.m. (7:30 a.m. ET).

Karzai escaped unhurt when Taliban militants opened fire at a military ceremony in Kabul on Sunday commemorating Mujahedeen Day -- the 16th anniversary of Afghanistan mujahedeen fighters' overthrow of the Soviet-backed regime. The attack killed an Afghan lawmaker, a tribal leader and a child. E-mail to a friend

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