The stadium fell silent as the clock ticked to 1504 GMT, marking the time of the crash on an icy runway in Germany six decades ago.
There were also ceremonies in Munich and Belgrade to mark the anniversary of the tragedy, which happened when the plane carrying Matt Busby’s youthful team back via Munich from Belgrade on February 6, 1958 crashed on its third take-off attempt.
United’s players were celebrating reaching the European Cup semi-finals but the crash destroyed one of the finest teams in the club’s history, killing eight players and three members of the club’s staff.
Twenty-three people died in total, including eight journalists, and there were 21 survivors.
Charlton and Gregg, the only survivors from the group of players who lived through the crash, were both at the ceremony attended by more than 4,500 supporters held amid snow flurries in the northwest of England, along with former United manager Alex Ferguson.
Current United boss Jose Mourinho and club captain Michael Carrick laid wreaths at the service, which was also attended by FIFA president Gianni Infantino and Liverpool great Kenny Dalglish.
Former goalkeeper Gregg, who spent time at the United training ground earlier on Tuesday, sang along with the hymn “Abide With Me” as the ceremony came to a close.
Gregg, who told the BBC Sport website that Tuesday’s service would be his final time at Old Trafford, said he did not believe the disaster had defined him or the club.
“I do not think what happened in Munich made Manchester United. It is a very large part of Manchester United history but it’s not all Manchester United,” said Gregg, who helped pull survivors from the wreckage.
“I have seen Manchester United through bad times and good times. I’m just very glad that Henry Gregg… was counted good enough to play for what I consider to be one of the greatest clubs in the world.”
Around 2,000 fans gathered in Germany for a fan-organised ceremony attended by club ambassador Denis Irwin.
It was attended by some surviving doctors and nurses involved in the treatment of manager Busby and his team, as well as Bayern Munich president Uli Hoeness and chairman Karl-Heinz Rummenigge.
“Football is about rivalry and friendship and respect. Being here today is a sign of respect for this big club and its unbelievable fans,” said Hoeness at Munich’s Manchesterplatz, named as a tribute to the victims of the air crash in 2008.
A memorial stone, laid in 2004, marks the site of the accident and the plaque bears the names of the victims.
Nicky Butt’s under-19 team joined club officials as a minute’s silence was observed at Partizan Stadium in Belgrade — the venue for the European Cup quarter-final between Red Star and United in 1958. They are due to play FK Brodarac in the UEFA Youth League on Wednesday.
– European glory –
The events of February 1958 are woven into the fabric of the club, who recovered to become the first English team to lift the European Cup 10 years later on a deeply emotional night at Wembley, with Charlton scoring twice.
Ferguson, just 16 years old at the time of the Munich crash, told MUTV: “I’d gone to the library straight from school swatting for an exam and I was training with the local junior team.
“When I got there, all the players were crying. I didn’t realise what had happened. When the news broke, it was really sad because I’d followed United at that time because of Matt Busby.”
“The day that is absolutely shown in red on this week’s calendar is on Tuesday, a day that marks the 60th anniversary of the air disaster,” Spanish forward Juan Mata wrote in his blog on United’s website.
“The victims will never be forgotten, they will always be remembered and will be a part of United’s history forever.”
British Prime Minister Theresa May paid tribute to those killed and injured at Munich during a speech elsewhere in Manchester on Tuesday.
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