Updated

KABUL, Afghanistan — Afghanistan's intelligence chief and interior minister resigned Sunday to take responsibility for allowing militants to elude a massive security operation and launch an attack on last week's national peace conference.

President Hamid Karzai's office said in a statement that he had accepted the resignations of Interior Minister Hanif Atmar and National Directorate of Security chief Amrullah Saleh because the explanation they gave for last Wednesday's attack was "not satisfactory."

At least two Taliban militants fired rockets at the conference where delegates discussed how to resolve Afghanistan's nearly 9-year war, then engaged in a gunbattle with security forces near the venue. None of the 1,500 delegates were hurt. The militants were killed.

Earlier Sunday, Interior Ministry spokesman Zemeri Bashary gave new details of the attack, saying the two attackers had eluded police providing security to the conference by dressing up as a couple -- one in street clothes and the other dressed in woman's burqa. The man hid a Kalashnikov rifle and a grenade launcher by wrapping them up in cloth like swaddled baby.

Bashary said that two major errors were made that allowed the couple to sneak through: insufficient intelligence reporting about the militant group they belonged to; and the failure of security forces to stop and search the couple as they walked almost 1 mile from a house they rented to the site where they launched their attack.

"It goes against all customs for a man to search a woman, so the enemy took advantage of this," Bashary said.

Afghan officials said they had arrested people from four different groups that had planned to launch attacks on the conference, known as a jirga, and police confiscated 550 pounds of explosives in the city during sweeps in the run-up to the meeting.

The statement from Karzai's office said the president had appointed Deputy Interior Minister Munir Mangal as acting interior minister and Engineer Ibrahim Spinzada as acting intelligence chief.