It was an emotionally trying moment for parents of victims of the serial killings in Nithari as they came face-to-face with the alleged murderers when they were brought to the Central Bureau of Investigation headquarters in New Delhi on Friday.

Ram Kishan, father of three-year-old victim Harsh, said he felt a sudden rush of uncontrollable anger when he sighted Moninder Singh Pandher, accused of killing 17 women and children along with his servant Surender Koli.

"We were put face-to-face with Moninder, but he avoided eye contact and did not talk," Kishan said.

Parents of some of the victims were brought to the CBI headquarters before being taken to AIIMS for obtaining DNA samples to be matched with those from skeletal remains found in a drain near Pandher's home in Nithari.

The parents and siblings of victims were taken to AIIMS by the Uttar Pradesh police on the directions of the CBI, which is not satisfied with the results of DNA tests conducted earlier at a local hospital.

The DNA samples were taken after the families of victims consented to the CBI's demand, sources said. Police in Noida had taken blood samples from parents of the victims on January 6.