Non-crew members present in cockpit of crashed Kaczynski plane

An investigation into the plane crash that killed the Polish president has said non-crew members were present in the cockpit of the plane.

President Lech Kaczynski and more than 90 others were killed in the crash last month.

One of the non-crew members has been identified, but has not been named.

The pilot's cabin door was open as the plane tried to land and the voices of the crew were difficult to identify.