Woman riding scooter killed in SF Market Street collision after wheel caught in train track: witnessA woman riding a scooter was killed Friday morning in a collision on Market Street in Downtown San Francisco, police say. A woman riding a scooter was killed Friday morning in a collision on Market Street in Downtown San Francisco, police say. A woman riding a scooter was killed Friday morning in a collision on Market Street in Downtown San Francisco, police say. A woman riding a scooter was killed Friday morning in a collision on Market Street in Downtown San Francisco, police say. SAN FRANCISCO (KGO) -- A deadly crash on a busy San Francisco street Friday is now fueling the debate over the safety of e-scooters.