"We can arrest Bharat Patel (Hardik Patel's father)... It has come to light that gun used for firing belonged to him and he is a licence-holder," police officer Vishwarajsinh Jadeja said.
The police registered a case under the Arms Act against Bharat Patel for violation of licence rules, he said, adding that eight persons had been arrested in the case so far.
Hardik Kirtibhai Patel - not to be confused with the Patel quota agitation leader - had submitted to the police a video which showed some members of Patidar Anamat Andolan Samiti dancing at a recent wedding in Viramgam, and one of them firing in air.
It was the wedding of Hardik Patel's cousin; the PAAS leader was also seen dancing in the video, though the FIR didn't name him.
Hardik Patel is, at present, out on a bail in two sedition cases filed against him by police in Ahmedabad and Surat.