Police on Tuesday informed an anti-terrorism court (ATC) in Karachi that they were still clueless about the perpetrators and facilitators of the attempted terrorist attack on the building of the Pakistan Stock Exchange despite the lapse of two-and-a-half months.

However, police said efforts were underway to identify and track down the facilitators and perpetrators of the June 29 attack on the country’s vital trading and business centre, in which all four attackers were killed in swift action by security forces.

A police sub-inspector and three security guards were martyred while seven others, including three police officials, were wounded in the exchange of fire.

A day after the incident, Prime Minister Imran Khan had said in the National Assembly that Pakistan had "no doubt" that India was behind the attack.

Police maintained that the identity of three of the attackers was established as Salman, Tasleem Baloch and Siraj Ahmed, but that of the fourth militant was yet to be determined.

This was disclosed by the investigating officer of the case in an A-class report filed with the administrative judge of the anti-terrorism courts on Tuesday.

An A-class report pertains to a case in which the accused persons are unknown or untraceable.

In the report, IO Inspector Chaudhry Arif Hussain of the Counter-Terrorism Department (CTD) stated that during the course of the investigation "all-out efforts" were being made to trace the perpetrators of the attack and their facilitators.

He said letters were issued to the relevant departments for the purpose of identification of the four slain attackers, their blood samples were sent for DNA testing and the weapons used by them in the attack were sent for ballistic examination. He added that letters were also written to the authorities concerned with regard to the security plan of the city's South district and to determine the genuineness of the claim of responsibility by the Balochistan Liberation Army (BLA).

According to the IO, the mobile phones used by the attackers were also sent to the Federal Investigation Agency to check their social media, Instagram and other accounts. “But most of the reports are still awaited,” the officer admitted in the report filed two-and-a-half months after the high-profile attack.

The IO maintained that the offence had been fully proven against the slain attackers in light of circumstantial and other evidence, but since they were killed in the 'encounter' with security personnel, the case could not be taken forward against them.

The investigation report was being filed under Section 173 of the Criminal Procedure Code because the stipulated time of investigation had lapsed, the officer said.

He requested the administrative judge to accept the A-class report, saying legal action would be taken against the unknown facilitators and perpetrators of the attack "if they were arrested in the future".

The judge accepted the A-class report and transferred the case to the ATC-XVI judge for its disposal.

A case was registered under Sections 302 (premeditated murder), 324 (attempt to murder), 353 (assault or criminal force to deter public servant from discharge of his duty), 427 (mischief causing damage to the amount of fifty rupees), 102 (commencement and continuance of the right of private defence of the body), 109 (abetment) of the Pakistan Penal Code read with Section 23(1)-A of the Sindh Arms Act, 2013, read with Section 6-2(I) of the Anti-Terrorism Act, 1997, and Explosives Act, 1908, on behalf of the state at the CTD police station.