Nine family members of Nong Chompoo, a three-year-old girl who was found dead near her home in Mukdahan in May, have taken a lie detector test to help police conclude their months-long probe into her death.
A source close to the investigation said uncle-in-law Chaiphol Wipha and his wife Somporn Lappho were yesterday brought to the Office of Forensic Science in Pathum Thani for a polygraph test.
From Monday to Thursday, seven other family members, including the victim's parents and siblings, were brought in to take lie detector tests, and were expected to be questioned for several hours, the source said.
Mr Chaiphol and Ms Somporn were to be questioned separately, and psychologists were to be present to observe, the source said before the couple were questioned.
Last year, Mr Chaiphol was interviewed by local television stations many times as they tried to shed light on Nong Chompoo's case. He was among several key suspects.
Yesterday was the first time Mr Chaiphol had undergone a lie detector test, the source said, noting the investigation into the victim's death hit a dead end months ago.
While the test results are not considered conclusive, it is part of the legal process, the source said.
The source noted law enforcement agents may be able to conclude the investigation by the end of this month.