With rescue efforts continuing at the scene in the Rajkot district, the local mayor told Reuters the death toll was expected to rise.
"Our focus is on rescue operations and saving lives. We will ensure strict action is taken against the people who are responsible for this incident," Mayor Nayana Pedhadiya said.
Television images showed a massive fire engulfing the TRP game zone and thick clouds of smoke emanating from the site on Saturday night (local time).
The entire structure was gutted in the blaze.
A police official at the local civil hospital said some of the bodies were charred beyond recognition.
Prime Minister Narendra Modi posted on social media platform X that the local administration was working to provide assistance to those affected.
"Extremely distressed by the fire mishap in Rajkot. My thoughts are with all those who have lost their loved ones," Modi said in the post.
The district's chief fire officer, IV Kher, said firefighters had almost brought the fire under control.
"The cause of the fire is yet to be ascertained," he told Reuters.
Gujarat Chief Minster Bhupendra Patel said an investigation into the incident had been handed to a Special Investigation Team (SIT), and television reports said two people had been detained by Rajkot police in connection with the incident.
