It has been four days since a small plane slammed into Beijing’s tallest skyscraper, killing the pilot – the only person on board – and wounding 13 others, but it’s still unclear why, and how, that happened.

A 60-word report detailing the basic facts in state-owned Beijing Daily is the only official statement China has published so far on the crash, which happened just a few kilometres from Zhongnanhai, the Communist Party’s headquarters.

Friday’s collision left holes on the side of the 109-storey CITIC Tower, which have since been boarded up. Dramatic footage of the incident has been scrubbed off the internet. At least three aviation firms tell the BBC they’ve been told to suspend light aircraft operations but declined to elaborate, saying they had been instructed not to discuss it.