According to news sources, today a PIA Boeing 777 Islamabad to Jeddah post-Hajj ferry flight landed in Karachi due to some technical problem with aircraft's engine number two. The aircraft was not carrying passengers. However, such ferry flights often carry cabin crew for serving passengers of post-Hajj flight from Saudi Arabia to Pakistan.
Probably it's PIA Boeing 777-200ER registration AP-BGK that landed at Karachi at 8:39 AM as flight PK-3011 from Islamabad from where it had departed at 6:55 AM.

Source:
flightradar24.com
Earlier, AP-BGK had arrived in Islamabad at 10:46 PM on August 27 as flight PK-742 from Jeddah.
https://www.flightradar24.com/data/aircraft/ap-bgk
Abbas