Afghan security forces arrested Kamal Uddin just 24 hours after the attack.

Intelligence officials said that a Pakistani mobile phone chip, also known as SIM card, had been found at his house.

The intelligence was released on the same day a suicide bomber detonated his explosives outside a US military base in Kabul, wounding six Afghan civilians and eight American troops. 

The Taliban claimed responsibility for Tuesday's attack.

Co-ordinated attacks

The January 18 attacks, said to be the most co-ordinated offensive on the capital since the US-led invasion in 2001, took place while Hamid Karzai, the Afghan president, was swearing in some of his cabinet ministers.

At least five people were killed and about 38 more wounded in the protracted gun battles that followed.

The Serena Hotel, which is frequented by foreign journalists, was also targeted.

In the wake of the attacks, Afghan security forces won some praise from their international counterparts for dealing with the incident.

The Haqqani network has carried out attacks in Kabul before, and US commanders have identified group as one of the biggest threats to US forces in Afghanistan.

The network, which was initially nurtured by the US's Central Intelligence Agency, has carried out attacks on foreign forces across the majority of eastern Afghanistan.

David Chater, Al Jazeera's correspondent in Kabul, said: "The interesting thing about the Haqqani network is that they are one of the most deadly and effective groups fighting alongside the Taliban, with close links to al-Qaeda."

The Haqqani network has also been connected to Pakistan's spy agency, the Inter Services Intelligence, or ISI.

International conference

Kamal Hyder, Al Jazeera's correspondent in Islamabad, said Pakistan was unlikely to accept any responsibility for attacks such as the one in Kabul.
 
"Despite the fact that the Afghan intelligence says it has uncovered a plot that was planned in Pakistan ... the Pakistanis are not convinced that operations being carried out on the Afghan side of the border are planned in Pakistan," he said.
 
"They will tell you that Jalaluddin Haqqani is a widely respected commander of the Taliban. He enjoys grassroots support in Paktia, Pakitika and Khost province and therefore for them to plan an operation inside their territory, or in Kabul, is not a problem."

Tuesday's announcement was potentially embarrassing as Karzai was meeting regional leaders including Asif Ali Zardari, the Pakistani president, in the Turkish city of Istanbul for a conference on Afghanistan.

The talks, also attended by David Miliband, the British foreign secretary, form part of the build-up to a conference in London where Karzai hopes for Western support for his strategy of encouraging Taliban fighters to lay down their arms with the promise of jobs and money.

Senior officials from Iran, China, Tajikistan and Turkmenistan are among those attending the conference, as well as observers from the US, Russia and international organisations.