Based on leads so far, police believe only one individual was involved in the murder of six-year-old autistic boy Zayn Rayyan Abdul Matiin from the Idaman Apartment in Damansara Damai, Petaling Jaya, last week. br br Meanwhile, almost a week since the body of the six-year-old was found, Apartment Idaman remained eerily quiet, with most neighbours tight-lipped when asked about the incident, but were hopeful that the perpetrator would be caught.