A Russian-owned civilian helicopter crashed during takeoff at southern Afghanistan's largest NATO base Sunday, killing 16 civilians in the latest in a string of deadly aircraft crashes in the country.

A U.S. military helicopter also made an emergency landing in the country's east. A military spokeswoman said there was no insurgent fire involved.

There were no indications that the crash of the Mi-8 helicopter at Kandahar Airfield was caused by hostile fire, military officials said.

A NATO statement said 16 people died in the crash and that the conditions of five additional casualties weren't immediately known.

No military personnel were wounded or killed, NATO said. There was no information provided regarding the identities of the passengers and crew, but a military official told CBC News that no Canadians were on board.

The Russian news agency Interfax said the Mi-8 was owned by the Russian air company Vertikal-T. Interfax said there were 20 people aboard the craft and the survivors included three crew members and two passengers. The discrepancy in the death counts could not immediately be explained.

Civilian helicopters ferry contractors to military outposts

The Mi-8 helicopter can seat up to 24 people, said Capt. Glen Parent, a spokesman for the NATO-led force in Kandahar. Civilian helicopters help ferry civilian contractors and supplies to small military outposts across Afghanistan.

In a second helicopter incident in the country's east, a U.S. military chopper made an emergency landing in Kunar province, the military said in a statement. U.S. military spokeswoman Lt.-Cmdr. Christine Sidenstricker said no enemy fire was reported near the helicopter.

Personnel on the helicopter were taken to a medical facility for treatment, but no other details were released.

The two incidents came after a spate of recent aircraft crashes in Afghanistan.

A U.S. air force F-15E Strike Eagle fighter jet crashed early Saturday in central Afghanistan, killing two crew members. U.S. officials say insurgent fire did not bring down the plane.

Last week, Taliban militants downed an Mi-6 transport helicopter in southern Afghanistan, killing six Ukrainian civilians on board and an Afghan child on the ground.

Earlier in July, two Canadian soldiers and one British trooper were killed in a helicopter crash in Zabul province. Officials said that crash did not appear to be a result of hostile fire.

Elsewhere in the country, the Afghan Defence Ministry said 35 militants were killed during a joint operation by Afghan and coalition troops in the Shah Walk Kot district of Kandahar province early Saturday. The mission included the use of air strikes, it said in a statement.

A spokesman for the ministry, Zahir Murad, said he did not know how defence officials knew that 35 militants had been killed, and there was no way to independently verify the number.