The incident took place around 5 PM. Police lobbed teargas shells to disperse the crowd and resorted to mild lathi-charge, even as the victims alleged that the force did "nothing to help" them.
The victims also claimed that the attackers were residents of Samter village, who wanted to "avenge" the arrest of 12 persons in connection with last month's Una Dalit flogging case.
The 20 victims, who are from Bhavnagar district, had gone to Una on their motorcycles along with others. They were returning home after hoisting of a tricolour by Radhika Vemula, mother of Dalit scholar Rohith Vemula who had committed suicide in Hyderabad, and Balu Sarvaiya, father of one of the victims of Una Dalit flogging incident, in the presence of JNU student leader Kanhaiya Kumar.
The mob stopped and attacked them at Samter, which falls on Una-Bhavnagar road and not far from Mota Samadhiyala village, where seven Dalits had been brutally beaten up by cow vigilantes last month.
"Police fired tear gas shells to quell a violent mob at Samter this evening. When they refused to disperse, police also resorted to mild lathi-charge," an official of Gir-Somnath police control room said.
Mavjibhai Sarvaiya, who survived the attack, alleged they were attacked by residents of Samter village.
"Out of the 30-odd persons arrested till date in the Una Dalit thrashing case, 12 persons belong to Samter, which is 11 km from Una. Around 200 Dalits, including me, had come to Una on our bikes to attend the rally. When we were returning, Samter residents blocked the road and thrashed us mercilessly," he said.
"Though the police force was there, they were outnumbered by attackers, who are holding us responsible for the arrests of 12 of their men. At least 20 persons were injured and eight of them received grievous injuries. The injured have been admitted to hospitals in Bhavnagar and Rajula. One of our bikes was also set ablaze," Sarvaiya said.
He alleged that police did not help them during the time of the attack.
"It was a pre-planned attack, as all the alternate roads were also blocked by them. We were attacked in the presence of police. When the situation went out of control, the police fired some tear gas shells on the mob," alleged Sarvaiya.
Despite repeated attempts, no senior police officials were available for comment.
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