The Taliban assailants who waged daring co-ordinated attacks across Afghanistan on Sunday were part of a 200-member suicide squad, a lone suspected attacker captured by Afghan foces has reportedly confessed.
As new details emerged about the attacks, which included an 18-hour siege on key Kabul neighbourhoods, a senior Afghan intelligence officer told Al Jazeera that the captured attacker had admitted to being part of a larger team tasked with waging similar operations ahead of a major NATO summit on Afghanistan in Chicago.
The team, which includes Afghan and Pakistani suicide bombers, was trained by Badrdudin Haqqani in Miram Shah, Pakistan, according to the suspect.
Al Jazeera could not independently verify the claims.
Ryan Crocker, the US ambassador to Kabul, said there was "no question" the attacks were carried out by the Haqqani Network, a branch of the Taliban.
"There is no question in our mind that the Haqqanis were responsible for these attacks. We know where their leadership lives and we know where these plans are made," Crocker said on Thursday.
"They're not made in Afghanistan. They're made in Miram Shah, which is in North Waziristan, which is in Pakistan.''
Police across Afghanistan are on alert, Sediq Sediqqi, spokesman for the Afghan ministry of interior, told Al Jazeera, confirming the threat of similar attacks.
The revelations come a day after Rahmatullah Nabil, the chief of Afghan intelligence, told parliament his agency was expecting similar attacks and was prepared to foil them.
He linked the increase in attacks to seasonal vacation in Pakistani madrassas (Islamic schools) among others.
The Taliban have announced that the co-ordinated attacks are the beginning of their 'spring offensive'.
Hamid Karzai, the Afghan president, blamed failures of the Afghan "and especially NATO" intelligence forces for the attacks that involved more than 30 Taliban fighters and claimed four civilian and eight police lives, but praised Afghan security forces for minimising civilian casualties.
However, a senior Afghan intelligence officer told Al Jazeera that they had notified security forces about the threats to Kabul more than two weeks ago.
“In writing, we even told them about the building across the parliament that would be taken over," the official said, referring to the building across the parliament that the fighters stormed.
Sediqqi, the interior ministry spokesman, said the building that was attacked was not the one specified in the intelligence report.
Either the intelligence was not accurate, or the enemy altered the plans, Sediqqi said, adding that the building that had been mentioned had been under the surveillance of security forces.
Javed Kohistani, a security analyst and former intelligence officer, told Al Jazeera that the intelligence agency was not prepared for the changing nature of the conflict in Afghanistan.
"They don’t have the structure, funding, and the necessary authority and backing against an enemy that trains and equips outside our borders," Kohistani said.
"There is no incentive and morale either - because the enemy is not clearly defined, and the political leadership keeps on shifting about the definition."
While Afghan security officials have announced their readiness to face such threats, concerns remain about a lack of co-ordination between the forces.
"We had problems, everyone was issuing separate orders, firing from every direction - even MPs were firing from the parliament," a senior police commander involved in quelling one of Sunday’s raids told Al Jazeera.
From previous attacks, the Taliban have learned what weapons are most effective to bring into the city, he said.
"This is a relatively new phenomenon - that they launch many attacks at the same time, but we are prepared to fight it," the official said.
Another police official complained about the presence of civilian-clothed, armed intelligence officers, as well as bodyguards of politicans at the site of the operations.
"Sometimes, it is difficult to tell them apart from the attackers. They carry weapons, but they don’t have uniforms," he said.
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