ROCKLAND, Maine — A legal fight has broken out between two parties involved in a criminal case that began more than two years ago over the alleged theft of more than $1 million worth of lobsters from one of the state’s largest seafood cooperatives.

J.P. Shellfish Inc. of Eliot filed a lawsuit in December seeking a foreclosure on the St. George property of Robert E. Thompson and Cindy J. Thompson. The shellfish company claimed in its civil complaint filed in Rockland District Court that the Thompsons borrowed $125,000 and provided a promissory note in January 2014 that put their property up as collateral for the business loan.

The Thompsons failed to repay the money in July when it came due and have since failed to repay it, according to the lawsuit.

The Thompsons filed a response in court in which they deny the claims and argued J.P. Shellfish is barred from proceeding with the case because of procedural errors that include improper service of the lawsuit.

The case had been scheduled for a hearing Wednesday in Rockland but was postponed. No reason was included in the court record for the postponement.

Robert Thompson, 53, and John Price, 58, the owner of the Eliot seafood dealership, first became embroiled in a criminal investigation when Thompson was arrested in October 2012 by the Knox County Sheriff’s Office and accused of stealing a large amount of lobsters. Thompson had been the manager of the Spruce Head Fishermen’s Cooperative for 20 years before his arrest.

The cooperative filed a civil lawsuit against Thompson in 2013 alleging he stole more than $1 million worth of lobsters from members and sold them to J.P. Shellfish. That lawsuit later was dismissed with terms of the deal not being revealed.

The felony theft charge against Thompson was dropped by the state in May 2013 after the district attorney’s office said it did not want to turn over evidence to the defense because it could jeopardize a federal investigation, which included the IRS Criminal Investigation Unit.

That investigation led to Thompson’s pleading guilty Dec. 11 to federal charges — one count of tax evasion and one count of violating the Lacey Act which prohibits the illegal sale of seafood — and he is scheduled to be sentenced on April 16 in U.S. District Court in Portland.

Thompson remains free while awaiting sentencing. The more serious tax evasion charge carries a possible penalty of five years in prison and a $250,000 fine.

In October, Price was sentenced to 45 days in jail and fined $100,000 for illegally structuring cash deposits linked to lobsters purchased through side sales from members of the cooperative.

Price’s seafood business was the primary buyer of lobsters from the cooperative, which has about 56 lobstermen as members. Despite the conviction, the cooperative agreed to continue doing business with Price.