The site was found hacked on September 14 by a group of persons who posted some message about "OP Free Kashmir" and a complaint was lodged yesterday by the firm handling the portal, police said.
The case has been handed over to the Criminal Investigation Department (CID) for probe.
"We are investigating into complaint filed by web designing firm Squad M Technologies yesterday regarding the hacking of the Chief Minister's website by group of hackers claiming to be from Pakistan on September 14", CID sources told PTI.
Praveen Kumar, Managing Director of the firm which has been designing Shettar's personal website for the past two years, said "we noticed that the wesbite had been hacked on September 14... The (offensive) content was removed within five minutes and the IP address traced to Pakistan was also blocked."
He said initially they did not file a complaint but after a regional TV channel carried a report on the hacking, CID asked them to file a complaint as the group might have links with terrorists outfits.
The hacking comes weeks after Karnataka police busted a terror module and arrested 14 persons from Hubli and Bangalore with suspected links to Lashkar-e-Toiba and HuJI and claimed to have foiled their plan to target MPs, legislators and mediapersons besides leader of a Hindu outfit.