Over a week after a family in Sector 10 were taken hostage and robbed of cash and jewellery worth Rs 15 lakh,the police are now probing the involvement of a family acquaintance. The manner in which the heist was committed clearly points a needle of suspicion on someone known to the family,said a senior police officer. There has to be a specific reason behind the robbers targeting the house. It is neither a corner plot that is easily accessible nor is it owned by the super rich. We are looking at various angles now,including the involvement of some domestic help with the culprits, said the officer investigating the case. He added that the robbers were well abreast with the passage leading to the house and were also aware of where the cash and jewellery were kept. This cannot be treated as coincidence,said the officer,adding: We have inquired from the family about their domestic help and are looking into the case. The police also visited the residence of with more photographs of suspects,but failed to get any breakthrough. The CIA,too,has been roped in to examine the robbery even as sketches of suspects have been released across the state. The police,meanwhile,await the forensic report to arrive from Madhuban. Last Friday,eight assailants,including a woman,took a family of 13 hostage and robbed the house of cash and jewellery worth Rs 15 lakh.