A police helicopter carrying 12 people crashed in the eastern province of Tunceli, Turkey, on April 18, the local governor’s office has said, adding that the crash may have been caused by poor weather conditions, the Hurriyet Daily News reports.

The helicopter was carrying a judge, seven police officers, one sergeant and three crew members, the Tunceli Governor’s Office said in a statement.

Heavy fog in the region made the rescue operation difficult, Turkish media reports said.