UPDATED at 2:50 p.m. to include statements from St. Louis Regional Convention and Sports Complex Authority executive director Brian McMurtry

A majority of the $1 million spent this year on the failed riverfront stadium project was for work done before Jan. 13, when National Football League team owners voted to let the Rams relocate to Los Angeles.

But more than $240,000 was billed to the St. Louis Regional Convention and Sports Complex Authority for work done between March 1 and 31, two months after the plan had seemingly been shelved.

An invoice dated March 29 for $241,667 from HOK Inc. was designated for “design development.” HOK senior vice president Lance Cage, who signed the invoice, did not immediately return a call Tuesday afternoon, and an HOK project accountant declined comment.

Jim Shrewsbury, chairman of the authority board, said he did not know specifics of the expense.

Executive Director Brian McMurtry said in a statement Wednesday all of the money spent was for work done prior to the January vote. The statement does not explain the dates on the HOK invoice.