The daily Dawn reported Tuesday that former commando Kamran Ahmed and his brother Zaman were picked up by intelligence agencies.
Terrorists had stormed PNS Mehran in Karachi May 22 and destroyed two surveillance aircraft. The naval base siege lasted for 16 hours.
While in the navy, Kamran had served at PNS Mehran base. He was sacked about 10 years ago following a court-martial for assaulting a senior officer, the media report said.
The military court had also declared him unfit for the job.
Intelligence officials said they suspect Kamran was involved in the communication network of terrorists who attacked the Mehran base.
The brother's family members claimed they had nothing to do with any terror act.
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