Rescue workers searching the wreck of the luxury cruise ship off the Italian coast still hope they may find survivors a week after the tragedy.
As relatives of those missing laid flowers on the sea at the scene, coast guard officials have said there is still a slim possibility of finding trapped passengers in some parts of the ship.
Eleven people have been confirmed dead with 21 missing.
Rescue operations have resumed on the part of the 17-deck Costa Concordia still above water after being suspended when the ship began slipping off a rocky ledge into the open sea.
The liner crashed into rocks off the island of Giglio on the night of 13 January with 4229 people from 60 countries on board.
The company operating the cruise ship is facing a class-action lawsuit in the US.
Italy's consumer association Codacons and two US law firms said they would file the suit against Costa Cruises on behalf of the passengers.
They want at least $US160,000 for each passenger.
Costa Cruises, owned by US-based Carnival Group, has blamed the ship's captain for last week's crash.
Mitchell Proner, a lawyer with Proner & Proner, said: "Along with Codacons, we have formed an association and our firms are collectively going to be filing a suit in Miami, by Wednesday next week, on behalf of all the victims of the Costa Concordia disaster."