The Nigerian Civil Aviation Authority (NCAA) has suspended Nigerian airline Dana Air from operating flights in the country.

According to a statement by the airline, the reason for the suspension by the NCAA – whose boss was sacked by President Goodluck Jonathan last week – remains unknown.

The suspension comes six months after Dana Air resumed flight operations following the country’s worst crash in 20 years.

In June of last year, a Dana air flight arriving in Lagos flew directly into an apartment block on the outskirts of the city – killing 163 people, including everyone on board the flight and ten people on the ground.

In response, an investigation was launched to determine the cause of the crash – the pilot having reported dual engine failure shortly before the plane went down -, with the government also taking the step of banning the airline from operation until the results of the investigation were available.

However, the airline was allowed to start flights again in September, despite an inquiry into the cause of the crash not yet being complete.