Around 10 heavily armed militants, who attacked and destroyed the CID headquarters in Karachi on Thursday killing 21 people and wounding 140 others, were trying to free their detained men.
"The terrorists aim was to get their men freed from detention, but they failed," Sindh Chief Minister Syed Qaim Ali Shah told mediapersons after visiting the blast site on Friday.
Meanwhile, Pakistan Interior Minister Rehman Malik said that Lashkar-e-Jhangvi was behind Thursday's brazen suicide attack on CID building, located at a walking distance from the Sindh chief minister's house and two five-star hotels.
"Lashkar-e-Jhangvi is behind the attack on CID building at Karachi," he told reporters in Islamabad on Friday.
Soon after the attack, Tehrik-e-Taliban had claimed responsibility for the attack, warning more attacks if its demands were not met.
Several activists from LeJ and Pakistani Taliban had been rounded up in recent weeks in Sindh. Earlier this week, the CID had arrested six activists of the LeJ, one of the most violent anti-Shia groups with links to the Al Qaeda.
Inspector-General of Police Fayyaz Leghari said that according to eyewitness accounts they were around 10 militants involved in the attack and they came in two vehicles one of which carried explosives weighing around 500 kilograms.
He said militants first exchanged fire with the guards for around 15 minutes before driving the explosive laden car into the compound leading to the massive blast.
"We are in the process of investigations and we have found some clues but I can't share them with you right now," he told reporters after visiting the blast site.
He said that investigators were looking at footage collected from some six CCTV cameras which were installed in the CID building and other offices in close proximity.
Pakistan has borne the brunt of terrorist attacks in recent times with terrorists linked to Tehreek-e-Taliban or other banned outfits targeting buildings and installations of security agencies, foreign missions and the government.
In many other cases, the terrorists have also directly targeted police training centres and mosques.
Analysts also believe the attack on the CID centre might have been an attempt to either free or kill the arrested militants but fortunately the CID had taken them to another investigation centre after getting their remand from court earlier in the day.
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