Carolina Hurricanes owner Peter Karmanos Jr. is being sued by three of his sons for more than $100 million (all figures U.S.)

The lawsuit was filed last week in a court in Oakland County, Michigan, where Karmanos Jr. lives.

The sons say their father did not repay a loan he took out in 2013 from a limited partnership he created with them.

The lawsuit states a son sent Karmanos Jr. a notice of default on April 21 demanding a $4.3 million payment on the loan within 30 days or else the entire balance of $105 million would be due immediately. The lawsuit says no payment was made. None of the allegations have been proven in court.

Peter Alter and Ethan Holtz, the Michigan-based attorneys representing the sons, did not respond to requests for comment. Hurricanes spokesman Mike Sundheim declined comment.

The lawsuit states the partnership was formed in 1996 as a way to transfer stock and other securities from Karmanos Jr. to sons Jason Karmanos, Peter Karmanos III and Nick Karmanos.

The lawsuit also states from 2000-13, Karmanos Jr. "entered into various loan and credit agreements, obtaining tens of millions of dollars in loans and advances from various banks and the NHL, upon information and belief, to be used to support the Hurricanes" and used the partnership's assets as collateral.

It says Karmanos Jr. borrowed $69.7 million from the partnership in April 2009 and promised to repay it plus interest by either December 17, 2017 or within 365 days of the elder Karmanos' death, whichever came first. The loan of $101.3 million taken in 2013 was to be repaid by June 29, 2022 or within a year of his death.

Jason Karmanos worked in the Hurricanes' front office for 15 years before he was fired in September 2013, with Karmanos Jr. at the time saying it was a "family matter." The Pittsburgh Penguins hired him as vice-president of hockey operations a year later.