The assassinations of the Taliban supreme leader's brother and other top Taliban leaders have been linked to the money supply chain of the group's illicit drug trade.
'It is clear for us that Iran bears responsibility for this attack. There is no other explanation,' the leaders of France, Germany and Britain said.
Discontent and divisions among the Afghan Taliban leaders are growing, and combined with the group's increasing unpopularity among Afghans, the group is steadily weakening.
Following a crackdown on various factions of the TTP across the country, the militants have shifted their hideouts to provinces in neighbouring Afghanistan.
A TTP commander sent a number of officials and local leaders threatening letters demanding loyalty to the group. The government is hunting down the perpetrators.
Mehsud, in a book titled Inqilab-e-Mehsud released in December 2017, detailed the TTP's extortion, kidnappings for ransom and assassinations.
Instead of choosing a peace deal finally within sight after 18 years, the Taliban decided to use Afghan lives as bargaining chips. Now Taliban leaders are paying for their thirst for violence.
The Financial Action Task Force (FATF) is set to review Pakistan's efforts over the past year in mid October.
Defense and Martyrs Day was observed Friday in Pakistan.
Police have orders to ensure the security of worship places and religious gatherings during the holy month.