All the forensic tests on the two suspects in the Noida serial murder case drew to a close after the final narco-analysis test on prime accused Moninder Singh Pandher ended at the Directorate of Forensic Science on Tuesday night.

"The narco-analysis of Pandher has been completed. With this all the three forensic tests (polygraphy, brain finger printing and narco-analysis) on Pandher have been completed," Director DFS J M Vyas told reporters.

"However, the two (Pandher and his servant Surender Kohli) will be called for a routine follow-up on Wednesday and then we will decide when to allow them to return," he said.

When asked when DFS will come out with the findings of the forensic tests, Vyas said, "All the data (from the three tests) has been taken and its analysis will take some time. It is a time-consuming process. We will analyse the data of all the three tests and form a final report."

"We have just completed conducting the tests. We will analyse the data and only then come to any conclusion," he said refusing to divulge any information on the details of the tests.