At least 16 civilians were killed Sunday when a helicopter crashed on take-off at a military base in southern Afghanistan, a NATO spokeswoman told AFP.

"We can confirm that 16 civilians were killed in the air crash and we have information that we have five (other) casualties. The status of these casualties are unknown," said Lieutenant Commander Sam Truelove.

"We can confirm also that no military personnel are among the casualties," said Truelove, a spokeswoman with the NATO-led International Security Assistance Force (ISAF).

ISAF did not reveal the nationality of those killed in the crash.