"Judicial Magistrate First Class at Mapusa remanded the nine accused to five-day judicial custody and were sent to a correction facility at Colvale in North Goa district," Calangute police inspector Jivba Dalvi said.
The other two accused, who are juveniles, aged 15, have been sent to a protection home near Panaji, he added.
The victims - 17-year-old boy and his 16-year-old sister - were on May 29 sitting in a shack at the Baga beach in North Goa while their parents were having food nearby.
At that time, a group of 11 visitors, who arrived from Pune district in the neighbouring Maharashtra state, started clicking pictures of the girl, Mr Dalvi had earlier said.
"When the boy objected to the group taking photos of his sister, they allegedly slapped and beat him," he said, quoting the complaint filed by parents of the siblings.
Besides the two juveniles, the other nine accused are in the age group of 18 to 30 years, police said.
The accused included some students and salesmen working in different companies.
Offences were registered against all the accused under IPC sections 354 (molestation), 143 (unlawful assembly), 147 (rioting) and 323 (causing hurt), and relevant provisions of the Goa Children's Act, the police added.
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