Eighteen people have died in a Russian helicopter crash in north-western Siberia, officials say.
Russian media quoted sources as saying that three crew members and 15 passengers were killed.
"The first take-off was carried out by a Mi-8 with an external cargo suspension without passengers on board, the second take-off was performed with passengers who were workers on shifts at the oil station", the ministry said in a statement.
Russian news reports said all the passengers killed are believed to have been working for a subsidiary of the state oil company Rosneft.
The second helicopter was able to land safely. "As a result it fell, broke apart and caught fire", the watchdog said, adding weather conditions were normal.
The Interstate Aviation Committee, which oversees civil aviation in much of the former Soviet Union, said the Mi-8 helicopter collided with the load being carried by another helicopter.
A well-informed official in the law enforcement agencies told TASS the helicopter had taken off from the town of Igarka, located on the River Yenisei to the north of the Arctic Circle. The criminal investigators of the Main Directorate of Criminalistics of Russia's Investigative Committee were sent to the scene, the committee said in a statement.
The crash comes four months after another fatal accident involving an Mi-8 in eastern Russian Federation, which killed six people.
'Utair's Mi-8 helicopter 25640 was flying from Vankor to Kharkasale, ' said an spokesman for Russia's emergencies ministry.
The Mi-8 helicopter crashed in the Krasnoyarsk region of Siberia.