Afghan intelligence agents netted a group of 17 men including a foreign national in connection to the suicide attack against the German embassy and five others in Kabul that killed 20 people, an Afghan spokesman said.
A Pakistani extremist group is believed to have carried out the bomb attack in Kabul
Five people including four civilians and one US soldier were killed and more than 20 others including a German diplomat were wounded in a suicide attack that took place in front of German embassy in Kabul city in January 17.
"It was one of the most dangerous networks," Sayed Ansari, spokesman for the National Directorate of Security, told a news conference in Kabul on Tuesday.
Pakistani militants among the suspects
The blast that killed 20 people was just one of many
He said the 17 suspects including a militant named Yasir, a Pakistani national and an explosive forging suicide-car-bombs and other explosive devices, confessed they were behind six suicide bombings in Kabul city since March 2007.
Around 20 people were killed in the six attacks in Kabul city and more than 120 others were wounded, he said.
According to one of the alleged confessions from one of the group, the bomber who carried out the attack against German embassy was identified as Abdullah, a citizen of Pakistan, Ansari said.
He said the group members were detained in different locations in Kabul city over three days in late January, adding that three of the organizers were still at large and believed to be in Pakistan.
Ansari told the DPA news agency that the German embassy was the "prime target" of the bombing.
Harakat-ul-Mujahideen, a militant group based in Pakistan and Haqqani network, an associated group of Taliban, were behind the attacks, he said. "All the planning and coordination for the attacks was done in other side of the border, in Pakistan."
Attack and arrest prove Pakistan involvement, claim officials
Afghan officials blame pro-Taliban Pakistani militants
Afghan officials have repeatedly claimed that the insurgency in Afghanistan is led and coordinated from safe havens inside the tribal areas of Pakistan, and have called on international forces to focus their anti-terrorism war on those sanctuaries.
An unknown phenomenon in Afghanistan until 2003, suicide attacks have become a common tactic for the Taliban militants, who were driven from power in late 2001 in a US-led military invasion. The militants were responsible for more than 120 suicide bombings in 2008.
In the latest series of such attacks, 21 police officers were killed and around 20 others were wounded, when a bomber targeted a police training centre in southern Uruzgan province on Monday.