JACKSON (AP) — Biofuel maker KiOR said Friday that the $1.8 million loan payment it missed to the state of Mississippi means it now owes more than $312 million immediately.

The company was supposed to make the payment to the Mississippi Development Authority by midnight Wednesday, the end of a grace period following a deadline of Oct. 31. No money was received.

Even before Wednesday, Mississippi sent a default notice saying KiOR owed the $69.4 million in principal, and $9 million-plus in interest trigged by the default, for a total of $78.6 million.

KiOR, based in Pasadena, Texas, borrowed $75 million from Mississippi to build a refinery in Columbus meant to make fuel from wood chips. But the $230 million plant never worked as designed and KiOR laid off almost all of its workers.

If payments had been made regularly, Mississippi would have charged no interest. The state had already delayed the deadline for the $1.8 million payment by 120 days, in exchange for a $250,000 payment. At the same time that extension was signed, KiOR hired investment bank Guggenheim Partners to sell the company or raise money.

KiOR said in a Friday stock filing that the default notice triggered provisions making another $234 million in loans immediately due in addition to what it owes Mississippi. Company officials did not respond to phone calls and emails Friday seeking comment.

“MDA was aware of the potential for cross default when the notice letter was sent to KiOR,” authority spokeswoman Marlo Dorsey wrote in an email. “Throughout this process, MDA has taken the necessary steps to protect the state’s rights and remedies.”

One of the other lenders, an investment fund run by the Canadian province of Alberta, declined comment.

An entity controlled by financier Vinod Khosla loaned KiOR another $1.1 million Friday, but it’s unclear what KiOR will do next. Mississippi has not sought to foreclose, a move that could force KiOR into bankruptcy and entangle the plant in litigation. State officials have been seeking a quick sale, hoping to find a buyer who could pay some of the debt and create jobs.

By Friday evening, the company had not declared bankruptcy where it’s incorporated in Delaware, where it’s based in Texas or where its plant is in Mississippi.

The wait could mean a buyer is near for the Columbus plant. Dorsey said MDA has signed a confidentiality agreement, a sign that someone may have serious interest in a purchase.

“MDA is working closely with its counsel and financial advisors to evaluate all options with the intent of finding the best solutions for the state in regard to the KiOR Columbus project,” Dorsey wrote. “MDA continues to assess any and all rights and remedies it has available and will provide updates once next steps are fully determined.”

The company’s shares were delisted from the Nasdaq exchange Thursday and closed at 7 cents in over-the-counter trading Friday.