The Gurugram Police has detained the gardener of Ryan International School, Harpal Singh, who is a key witness in the murder of class II student and is likely to arrests some more persons, a senior SIT officer said.
The Gurugram Police's Special Investigation Team (SIT) detained the gardener on Wednesday.
The 7-year-old Pradyuman Thakur was found with his throat slit in the washroom of the school last Friday. The school bus conductor Ashok Kumar has emerged as the prime suspect and has been arrested.
"The SIT does not want to leave out a single piece of evidence which can be important and work as a key breakthrough for us to solve this case. With three days left for submission of charge sheet in court, we have got possible positive leads against ... Ashok Kumar," a senior SIT officer told PTI.
"Some more arrests are likely to be made," he said.
SIT teams on Wednesday searched the school here for clues while a CBSE panel also inspected the premises to examine loopholes in security arrangements.
Besides Harpal Singh, the SIT has questioned 17 persons including section in-charge Anju Dudeja, suspended acting principal Neerja Batra, former principal Rakhi Verma, bus driver Saurabh Raghav, bus contractor Harkesh Pradhan and eight security guards.
The officer said all suspects who are on the police radar, whether it is the suspended school principal, senior management officials or staff members, are being questioned.