A light aircraft crashed into a high-rise building in central Beijing on June 26, killing the pilot and injuring 13 people.

Authorities said a single-engine, two-seat light sport aircraft collided with a high-rise building near Beijing’s East Third Ring Road at 5:55pm local time, but have released few details about the circumstances surrounding the crash.

A week later, many questions remain unanswered.

Chinese authorities have not explained how the aircraft entered airspace near one of the country’s most heavily controlled and politically sensitive areas.

Questions about the identity of the pilot swirled in the aftermath, only being confirmed by authorities almost a week after the crash.

An investigation is under way.