Wasim Ahmed told a news conference that four masterminds of the attack have been arrested with the help of mobile phone data. He said that the accused men have confessed to the crime.
The bomb attack on the procession killed 45 people and injured 100 others, the police chief said.
A Taliban commander Asmatullah Shaheen had earlier claimed responsibility for the attack but later, Taliban central spokesman Azam Tariq denied any role.
The police chief said that those arrested are: The group leader, Murtaza alias Shakil, Shakaif Khan, Wazir Muhammadand Murad Shah. He said a bomb was also recovered on the information of the accused.
Wasim said that the police had been monitoring activities of the group members after the attack and arrested them after collecting enough evidences.
“It was a challenge for the Karachi police and we worked day and night to reach the suspects,” he said.
Wasim said that several other members of the group had fled Karachi after the attack and have moved to South Waziristan tribal region. He added that police had taken enough security measures but the terrorists succeeded to carry out the attack.
The police chief said that action has been taken against several police personnel for their negligence
He said that the Karachi-based Jundullah terrorist group is involved in several terrorist acts as well as in bank robberies and other crimes. He said that the group has no link with any political party but a religious extremist group.
The police chief said that Karachi had been peaceful over the past one year and the police arrested 66 terror suspects and killed 6.
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