India blames Pakistan-based militant group Lashkar-e-Taiba (LeT) for an attack that killed seven of its citizens in Kabul on February 26, a government source said on Thursday.
"The LeT is responsible. We have no doubt about that," the source told reporters on condition of anonymity.
He said the group, which India also holds responsible for the Mumbai attacks in November 2008 that left 166 people dead, operated out of Kunar province, northeast of Kabul.
In a call to AFP last month, an LeT spokesman denied any involvement in the February attacks, which saw gunmen launch a bomb and gun assault on hotels in the Afghan capital that killed 17 people in total.
The spokesman said the group had no network in Afghanistan.
Analysts believe India and Pakistan, implacable South Asian rivals, are locked in a new struggle for influence in Afghanistan, which is fuelling attacks on Indian interests there.
New Delhi has poured money into Afghanistan and has become an influential partner of the government in Kabul after giving 1.3 billion dollars in foreign aid.
India says the LeT has links with and support from the Pakistani army and intelligence services -- accusations strongly denied by the government in Islamabad.
Indian officials in Kabul have said a December 15 suicide car bombing that killed eight people also targeted Indians, although former Afghan first vice president Ahmad Zia Massoud had a home in the same street.
In other attacks, the Indian embassy was hit on October 8 last year, with the deaths of 17 people, and on July 7, 2008 when more than 60 people were killed.