Raju Das alias Raja was arrested by police from Mahamayatala area of Garia last night, police said.
He was produced before a local court which remanded him to three days police custody.
Earlier two persons were arrested by police.
The girl a student of class VIII was gangraped twice within three days by a group of four neighbours, including a minor, in Sonarpur area of South 24 Parganas district.
Though the incident occurred late last month, it came to light on February 6 when the teenaged girl revealed the matter to her mother.
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Later, two others, of whom one is a minor, reached there and she was gangraped by the four, the police said.
The accused took photos of the act with their mobile phones and threatened the girl that they would circulate the pictures if she told anyone about the incident.
The gangrape was repeated on January 29 when she was going for tuition again, police said.
Her family members lodged a police complaint and two accused were arrested on February 6.