user: Question: What happened in Mazar-i-Sharif?
Columns: ['Date', 'Location', 'Nature of incident', 'Circumstances', 'Casualties']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['2007-05-19', 'Kunduz', 'Hostile', 'Suicide bomber attack', '3 KIA, 5 WIA']
SQL:

assistant: SELECT "Circumstances" FROM "Table" WHERE "Location" = 'Mazar-i-Sharif';