Police and intelligence agencies submitted an initial report to the Interior Ministry, which said four armed men entered the court complex and blew themselves up in two suicide attacks, according to local media reports.
What was left behind was streams of blood, shattered glasses, broken tables and photocopy machines besides walls bearing bullet marks.
Human tissues were lying at the crime scene with gory blood spots everywhere.
Firing broke out after the blasts and the attackers, aged between 20 and 25 years, fled the scene.
"There were two teams of attackers. They opened indiscriminate firing that made people run for cover," a lawyer, who requested not to be identified, at the court complex told PTI.
Other witnesses said three young gunmen were involved in the attack. The gunmen entered from one of the 16 entry points to the Court premises.
"They opened fire here," a witness said pointing towards a court room in which a female lawyer was shot dead.
Down the lane on the right was the chamber of Judge Rafaqat Ahmad Khan Awan. The glass window of his door was broken and on the left was another door which seemed to have been kicked open.
A local policeman guarding the crime scene pointed towards the area where the Judge was shot down.
Behind it was the spot where one of the attackers blew himself up.
"This is where the attacker threw the hand grenade," a policeman said pointing towards a crater.
The police recovered the body of the attacker which has been sent for further investigation.
One of the biggest handicaps in the investigation was lack of CCTV cameras inside the complex. The two scanning machines installed were also not working.
According to eyewitnesses, the firing continued indiscriminately for about 10-15 minutes.
Two of the attackers, cornered by security forces, were shot when they blew themselves up, sources said, while an unidentified number of gunmen escaped.
Image: A policeman cordons off the site of a bomb attack at the district court in Islamabad
Photograph: Zohra Bensemra/Reuters
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