(Newser) – Indian police plan to inject a controversial truth serum into the lone surviving Mumbai terrorist to try to prove his identity, reports the London Times. The narcotics-powered analysis could yield proof that the so-called "baby-faced gunman" is indeed from Pakistan, which India suspects but Pakistan doubts. Western agencies stopped using the method—usually a form of sodium pentathol—during the Cold War because of psychological side effects such as hallucinations and delusions.

Interrogators say the 24-year-old has been "verified" to be from rural Pakistan, but President Asif Ali Zardari said he is skeptical. An established link to the nuclear rival could force Pakistan to take action or face a US backlash. Indian police say they have recovered Pakistani grenades from the rubble and have ample other evidence. (Read more police interrogation stories.)

