We really don't know. Maybe he was alone and just had some sort of accident, like slipping near the edge of a balcony on a high - rise building. Or perhaps he was with someone who could have tried to stop him from falling, but failed. Without more details, it's impossible to say for certain whether he was alone or not.
The outcome depends on various factors. Maybe he was lucky and survived with major injuries that require long-term recovery. Or it could be a tragic event with fatal consequences. We need more information to know exactly.