CNN 's Antonia Mortensen contributed to this report . NEW : Warsaw 's main airport will remain closed overnight . The passengers `` stayed calm '' during the emergency landing , the airline says . Comment: It landed on its belly after problems with its landing gear .
NEW : Warsaw 's main airport will remain closed overnight . The passengers `` stayed calm '' during the emergency landing , the airline says . Comment: It landed on its belly after problems with its landing gear .