Nine pedigree dogs, belonging to the lawyer brothers from here, were put to sleep by Kuala Langat District Council officers on Sunday.
Six Rottweilers, two Dalmations and a bulldog were put down by lethal tranquilisers at the poultry farm in Sungai Gadung, believed to the scene of a quadruple murder.
The officers were seen entering the farm at 8.15am and left about two hours later with the carcasses in a pick-up lorry.
The source said police had told the district council to catch the dogs but the team despatched to the area decided to put the dogs down as they were aggressive.
The carcasses were taken to the Sungai Sedu landfill in Telok Datuk, near here, to be buried.
Meanwhile, scores of local and foreign tourists on their way to a nearby longan farm and curious onlookers tried to get into the farm where the murders allegedly took place.
They were, however, turned away by policemen.
Longan farm owner Lim Soon Beng, 40, said he had lost thousands of ringgit since the entrance to his 6ha farm was sealed to give way to police investigations.
"I have been losing between RM2,000 and RM3,000 a day as my produce could not be transported out and tourists were stopped from entering the farm."
The two lawyer brothers, aged 41 and 38, from here, and five others were detained to facilitate investigations into the murders of Datuk Sosilawati Lawiya, 47, her driver Kamaruddin Shansudin, 44, banker Noorhisham Mohammad, 38, and lawyer Ahmad Kamil Abdul Karim, 32.
The four were killed and burnt and their ashes scattered in rivers.
Police have found bone fragments, a cricket bat and a knife after searching the rivers.
The bone fragments have been sent to the Chemistry Department for DNA analysis and the results are expected this week.
Sosilawati, the founder of the Nouvelles Visages beauty line, and her three aides were believed to have met one of the lawyers before they disappeared on Aug 30.
They were allegedly murdered at the farm belonging to the lawyer. The farm has, among others, a clubhouse, chalet and an office.
Two teams are carrying out the investigations, one on the quadruple murder and the other on the disappearance of three people and the murder of a housewife.