A Ukrainian helicopter crashed into a Black Sea oil drilling rig on Monday, killing 19 of the 20 people aboard, a government spokesman said.
The MiG-8 passenger helicopter had been carrying workers to an oil rig some 70 km in the Sea of Azov near the Crimea peninsula, said Yury Avdeev, an official from the state-owned Chernomornaftogaz energy company.
The dead included 16 rig workers and three flight crew, Avdeev said.
One oil worker of the 20 people aboard the aircraft survived the fiery crash in critical condition, the Interfax news agency reported.
The aircraft's rotor struck a steel a fence rail on the rig during a landing attempt, causing the helicopter to flip over, slam into the rig, and burst into flames, said Iosif Vinsky, a Transport Ministry spokesman.
The remains of the helicopter were on fire for some ten minutes before the blaze was extinguished, the Interfax news agency reported.
The MiG servicing the government-operated Tavrida oil and gas field had received all proper pre-flight checks and was fit for flight, Vinsky said.
Weather conditions in the region had been rainy and windy prior to the accident, but flight conditions at the time of the accident had been "satisfactory," said Maryna Soroka, a government spokeswoman.
An investigation of the accident site involving motor boats clearing debris and divers checking for underwater stress damage to the rig's structure was in progress, she added.
The Azov Sea mishap came exactly one month after a Ukrainian Border Troops helicopter, also a MiG-8, smashed into the Black Sea near the Danube delta, en route to an island observation post.
Thirteen persons died and one passenger survived in the crash, caused by a combination of poor weather and pilot error, investigators said.