JONES ACT carrier Horizon Lines has agreed to pay US$45 million in fines over five years for antitrust violations in the Puerto Rico trade.

Horizon said US Justice Department prosecutors agreed not to pursue criminal charges against many senior managers, but made no promises concerning Horizon president and CEO Charles 'Chuck' Raymond, or his chief operating officer John Keenan, reported London's International Freighting Weekly, adding that a number of senior Horizon executives were also at risk of further charges.

Three former Horizon executives and two ex-Sear Star Line managers have already been charged and sentenced to prison terms, reported American Shipper.

Mr Raymond was retiring as Horizon president and CEO and would be replaced by Stephen Fraser while Mr Keenan was taking a "leave of absence" and would be succeeded by Brian Taylor from March 11.

Horizon Lines issued a memorandum of understanding with Puerto Rico and attorneys representing indirect purchasers on February 22 that it agreed to pay $1.8 million in exchange for a full release from further litigation.