Judicial authorities in Greece have jailed the captain and first officer of a yacht before a trial on arson charges related to a forest fire that is suspected of being caused by fireworks, according to a report. Both men have denied wrongdoing in connection with the fire on the island of Hydra—as have 11 other members of the crew who were also arrested but have since been released on bail with restrictions, Reuters reports. All 13 Greek crew members were arrested over the weekend after the fire erupted on Friday night, destroying a large swath of the island’s only pine forest before it was contained early Saturday. The vessel’s foreign passengers are no longer in the country. A legal source told Reuters that there was insufficient evidence connecting the crew with the case and that the unnamed captain was the first person to make authorities aware of the fire. The news agency also cited court documents saying witnesses described hearing sounds like fireworks at around 10:30 p.m. on Friday before seeing smoke and flames.