Massachusetts officials have issued subpoenas as they investigate why an IndyCar race pulled out of Boston before it even began.

State Attorney General Maura Healey has subpoenaed documents from the defunct Boston Grand Prix and the national IndyCar organization. Healey wants to know where millions of dollars in ticket sales and sponsor fees went.

The race was scheduled to be held Labor Day weekend, but organizers cancelled it in April. The race ran into public opposition and a wavering commitment from local leaders.

Grand Prix and IndyCar officials met at Healey's office Wednesday. Healey says she will sue unless Grnad Prix organizers disclose by June 27 how they will refund ticketholders.

Boston Grand Prix manager John Casey told The Boston Globe he believes the parties will reach an agreement.