By Hamid Shalizi and Mirwais Harooni
KABUL (Reuters) - Afghan President Hamid Karzai held talks with his Pakistani counterpart, Asif Ali Zardari, on Tuesday amid heightened tension between the neighbors and as some Afghan lawmakers raised fears that Pakistan's spy agency was behind recent assassinations.
Gunmen killed a top adviser to Karzai and a member of the Afghan parliament in Kabul on Sunday in an attack claimed by the Taliban, but some lawmakers accused the Pakistan military's Inter-Services Intelligence (ISI) spy agency of being involved.
A senior Pakistani security official in Islamabad said the allegations were "a figment of someone's sick mind".
Afghan Interior Minister Bismillah Mohammadi told parliament on Tuesday that the gunmen made phone calls to provinces in Afghanistan and Pakistan before and after the attack, but he did not name specific groups or people who may have been involved, officials said.
Daoud Kalakani, a former strongman and now a member of parliament from Kabul province, accused a top general in Pakistan's intelligence agency and two senior Taliban commanders of putting together a hit-list of influential Afghans.
"Those who fought and spoke against Pakistan's interference in Afghanistan and Taliban backed by Pakistan are now being eliminated," he said on Tuesday. "It is a very worrying sign for security and transition."
The Kabul attack on Sunday coincided with the start of a transition to Afghan security forces that will end with all foreign combat troops leaving the country by the end of 2014.
Some Afghan lawmakers have even expressed fears about attending parliament because of perceived threats against them, but they were reluctant to speak openly.
"It is very clear that Pakistan is meddling in Afghan affairs and government must adopt a sterner stance toward Pakistan," said Naeem Hameedzia Lalai, head of the Afghan parliament's Internal Security Committee.
Afghanistan has often blamed elements within the Pakistan government for supporting the Taliban-led insurgency, while Pakistan blames Afghanistan for giving refuge to militants on its side of the border.
Karzai and Zardari met in Kabul on Tuesday and spoke about the economic and security situation faced by the neighbors and agreed that they should not let anyone disrupt security in either country, Karzai's palace said in a statement.
Zardari also offered his condolences to Karzai on the death of his brother, Ahmad Wali Karzai, a powerful and controversial leader in southern Afghanistan who was assassinated by a senior bodyguard in his Kandahar home last week.
Recently ties have been further strained by cross-border shelling that Kabul says killed at least 42 civilians. Karzai has said he will not respond with force, over-ruling senior ministers who had sought permission to return fire.
Pakistan has repeatedly rejected the allegations of large-scale shelling, saying that only "a few accidental rounds" may have crossed the border when it pursued militants who had attacked its security forces.
Pakistan recently lodged a protest with Kabul over cross-border attacks by militants, calling for stern action by Afghan and NATO-led foreign forces against the insurgents.
(Additional reporting by Chris Allbritton in Islamabad, writing by Michelle Nichols, editing by Paul Tait)