"We have arrested a man working as an instructor with the school. Mustafa, alias Munna, aged about 30 to 32 years old is from Bihar and has been in Bangalore for 20 years, " Bangalore Police Commissioner Raghavendra Auradkar told a press conference.
Police said they also seized the man's laptop and a mobile, which are filled with pornographic material. "The laptop had videos of schoolchildren being raped downloaded from Internet. This shows his state of mind," the Commissioner added.
The accused will be produced in court on Monday where the police will seek judicial custody.
This is the first arrest in the case even though three persons were detained earlier. The police are still looking for another accused.
The arrest follows days of protest and online campaigns by furious parents.
The six-year-old first grade student was allegedly raped on 2 July at the Vibgyor High School in the city.
Her mother found out about the assault seven days later, when a private nursing home hinted that the child could have been raped.
Angry Parents in the IT hub have taken to the streets and social media, demanding tough action, not just against the alleged attackers but also against the school.
Parents have accused the school of gross negligence and putting the school's reputation ahead of children's safety.
The case has become a hot-potato with the opposition demanding the Home Minister K J George's resignation.
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