The plane disappeared from radar over the English Channel. It was last known to be flying near Hurd's Deep, an underwater valley which has a depth of more than 100 meters (328 feet). Argentina is asking Britain and France to resume the search. A statement from the office of President Mauricio Macri said the country's foreign minister would make a formal request to the two European nations.
As other high-profile figures like Argentine soccer stars Lionel Messi and Diego Maradona also joined calls for the search to resume, Halilhodzic expressed his anger at a news conference on Friday. "For me, it's a disgrace to stop like this. I don't think it's enormously deep not to be able to find it. It's an obligation these people have," Halilhodzic said. "It's a total disgrace. You can't leave it this way. To stop like this is unbearable and unacceptable. Can you imagine the family? Yesterday, did you see how his sister expressed herself?"
Speaking in Cardiff on Thursday, Sala's sister Romina said: "Please, please, I'm asking you — don't stop searching. They're alive." A growing social media petition, including some Argentina players, has also asked for the search to go on.
Messi wrote on Instagram: "As long as there are still possibilities, a hint of hope, we ask you please continue to look for Emiliano." Maradona also posted on Instagram, pleading for the search to continue, with the message: "Hope never dies."
Halilhodzic said: "I just have one message to those responsible, that they continue their search because it's disgusting to leave a situation like that. I can't imagine how his family is taking this."
The 66-year-old Halilhodzic was one of the best strikers in Nantes history, scoring 111 goals, and fans voted the former Yugoslavia international on to their greatest-ever team. Known as a strict disciplinarian, he admired Sala for his work ethic and constant desire to improve.
The player-coach partnership paid off, too. Sala was enjoying the best season of his career before he joined Cardiff this month, scoring 12 league goals in 19 games and cementing his high reputation among supporters as a hard-working and unselfish player.
Halilhodzic was visibly moved as he spoke about Sala. "I had a special relationship with this lad because we spoke a lot together, worked a lot together," he said. "The last thing he said to me was he regretted we could no longer work together and that remains engraved deep in my heart."
Nantes' French Cup game at Sannois Saint-Gratien on Sunday has now been postponed and moved to the following weekend. For now, the club has not employed psychologists to help the players cope with the Sala situation. But Halilhodzic said it was an option.
"I know that in certain situations like this people use them," he said. "It's difficult for me to judge the state of each player. If we need it, we can use this type of treatment. "I want us to stick together. If you see someone in distress you can help them, speak to them. I am asking everyone at the club to be even closer to the players, to talk together. I think this is the best way of getting through this."
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