Updated

The captain of a capsized cruise liner reportedly 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.

A state of emergency has reportedly been declared in Italy after an unidentified liquid began leaking from the Costa Concordia.

Sky News reports that protective barriers have been put in place around the ship, citing Italy's environment minister. The state of emergency declaration is to formally release funds to address the ongoing situation as anti-spill booms have been deployed to minimize potential safety risks.

An earlier estimate of 16 passengers missing was revised upward, to 29 missing, late Monday night by the Italian coast guard.

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The rescue operation on the cruise liner resumed Monday afternoon after a brief suspension, as fears grew for the people -- including an American couple and a 5-year-old child -- who remained 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 Monday morning, Sky Italia TG24 reported.

Three bodies were recovered and 4,200 people evacuated after the luxury cruise ship ran aground off the coast of Tuscany, sending water pouring through a 160-foot gash in the hull. Passengers complained the crew failed to give evacuation instructions and that a drill was only scheduled for this afternoon. Authorities still hadn't counted all the survivors, the Associated Press reported.

But the search resumed later Monday as wind and sea conditions improved.

"We have resumed operations after checking that the ship has stabilized," emergency services spokesman Luca Cari said.

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, U.S.-based Titan Salvage and Netherlands-based Smit are on site waiting to assess the ship.

The death toll from the disaster rose to six Monday morning as rescuers found a sixth body -- a male passenger wearing a life vest -- 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, ages 69 and 70.

Mark Toner, a U.S. State Department spokesman, said Monday that the U.S. Embassy to Italy has requested assistance from anyone with information regarding the Minnesota couple's whereabouts. State Department officials are in contact with relatives of the Heil's and are working with Costa cruise lines and Italian authorities to provide all possible assistance.

Anyone with information regarding their whereabouts is asked to email ItalyConcordiaUSC@state.gov, Toner said.

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

Passengers, including a 72-year-old former Argentinean judge Maria Ines Lona, maintained Monday that Schettino was to blame.

"Passengers who had been on the ship for days said he was partying, he was spending his time with women and drinking," she told reporters as she arrived at Buenos Aires airport.

The Associated Press and Newscore contributed to this report.