The rescue operation on the cruise liner shipwrecked off the Italian coast was temporarily suspended Monday after the ship began to slip, as fears grew for the 16 people — including an American couple and a five-year-old child — who remain missing.

The Costa Concordia, which crashed Friday killing six and injuring at least 42, moved 3.5 inches vertically and 0.6 inches horizontally from where it was stranded, due to rough seas, prompting search teams and divers to be evacuated, Sky Italia TG24 reported.

Meanwhile, Italy’s environment minister Corrado Clini said the environmental risk from the stricken Costa Concordia, which has 2,623 short tons of fuel on board, was very high, and called for urgent action to be taken to prevent the fuel leaking.

Experts from two ship salvage companies, US-based Titan Salvage and Netherlands-based Smit are on site waiting to assess the ship.

The death toll from the disaster rose to six earlier Monday morning as rescuers found a sixth body — a male passenger wearing a lifevest — on the second deck in the unsubmerged part of the ship, ANSA news agency reported.

The grim discovery came as friends and family prayed for the safe return of Minnesota couple Gerald and Barbara Heil, aged 69 and 70.

Relatives told myFOXtwincities.com that the pair, from White Bear Lake north of Minneapolis-St. Paul, were among those missing after the cruise ship crashed. They say they still have not heard from the couple.

The US Embassy in Rome said 120 Americans were estimated on board the cruise liner but two have not been accounted for.

Italian investigators launched a probe into what caused the cruise ship to run aground off the Tuscan shore as it passed the island of Giglio with 4,234 people on board.

The Costa Concordia’s captain, Francesco Schettino, was detained for questioning by police and could face multiple homicide charges. The ship’s operator Costa Crociere admitted Sunday that “there may have been significant human error” by Schettino that led to the disaster.

Speaking Monday, Costa Crociere chairman and CEO Pier Luigi Foschi said that based on initial assessments, it appeared that the ship was following a pre-programmed route before it crashed.
He told a news conference that, “this route was put in correctly. The fact that it left from this course is due solely to a maneuver by the commander that was unapproved, unauthorized and unknown to Costa.”

The captain allegedly sailed the ship close to the rocky shores of Giglio to please his head waiter who comes from the island, Italian newspaper Corriere della Sera reported Monday.

Officials and witnesses said earlier that the disaster may have been caused by a risky practice of close-passing the island of Giglio in a foghorn-blasting salute to the local population.

The captain defended himself Sunday, telling Sky Italia TG24 that the ship struck a rock that was not shown on nautical charts.

(Source: Fox News)