Afghanistan intelligence has said fighters smuggled over the border from Pakistan were responsible for a recent assault on government targets in the Afghan capital.
Officials in Kabul released video footage on Tuesday of a man arrested in connection with the attacks who said that the Haqqani network, a group of Afghan fighters based in Pakistan, were behind the offensive.
The man, an Afghan identified as Kamal Uddin, said in his alleged confession that there had been seven suicide bombers in the attack, which took place on January 18.
"I was in charge of two suicide bombers and took them to a shopping centre near the presidential palace," he said, noting that he had housed the suicide bombers and their co-ordinators ahead of the attacks.
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.
Co-ordinated attacks
The 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 minister.
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 America's Central Intelligence Agency, has carried out attacks on foreign forces across the majority of eastern Afghanistan.
International conference
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.
That makes Tuesday's announcement potentially embarrassing as Karzai is 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.
