It's one year since the attack on Manchester Arena that left 22 people dead, more than 250 injured, and countless more lives affected forever. Ariana Grande, who was playing a concert that night, tweeted her respects to the victims and their families, saying she was "thinking of you all... on this challenging day."
Various other tributes are being paid to the victims today, including a nationwide minute's silence at 2.30pm and a service at Manchester Cathedral followed by a singalong vigil. There will also be a special commemorative "Manchester Together" event in the city from 7pm, featuring more than 3,000 singers from local choirs, and bells will ring across the city at 10.31pm to mark the exact time the bomb was detonated.
Meanwhile, politicians, city officials, celebrities and people all over the world are paying their respects on social media, including Prime Minister Theresa May, Labour leader Jeremy Corbyn, Greater Manchester's Mayor Andy Burnham, Greater Manchester police and London Mayor Sadiq Khan.
Today my thoughts are with those in Manchester who were lost on that terrible night and their loved ones who have so bravely battled to rebuild their lives. All of you – and many more in this great city - are the very best of what this country stands for. https://t.co/AZNczePl5u— Theresa May (@theresa_may) May 22, 2018
Remembering the Manchester attack and sending love to their families. I think today it’s important to remember the power of the One Love gig and how it brought not just the city but the world together. Such a positive bolt of energy in a hard, dark time. 🐝💛— nick grimshaw (@grimmers) May 22, 2018
Today we #standtogether to remember those who lost their lives in the Manchester Arena attack a year ago. My thoughts are with their families and friends, the injured and the emergency services who responded on that night 🐝❤️ pic.twitter.com/e89SNDOoih— Scarlett Moffatt (@ScarlettMoffatt) May 22, 2018
A play is also being staged in memory of victim Martyn Hett, the 29-year-old who won the nation's hearts with his hilarious tweets and inventive sense of humour. #BeMoreMartyn – The Boy with the Deirdre Tattoo, which takes its name from the viral hashtag following the news of his death, is showing in Manchester from Monday 21st to Saturday 26th May before coming to London on Sunday 3rd June.
After Martyn Hett died in the Manchester Arena bomb last year, @hopetc set out to find out what #BeMoreMartyn means. Bringing to life some of Martyn’s most iconic pop culture references and asks audiences how they can make a difference to the people they love. #OnSale #theatre pic.twitter.com/dNXEQZlEWk— Hope Mill Theatre (@hopemilltheatr1) May 17, 2018
One year on. I bloody miss you so much @martynhett. Forever saved as Eileen Grimshaw in my phone. Today is going to be tough but I'll make sure there's a voddy and coke and vintage Corrie waiting at the end of it. Love you 💖🐝 #BeMoreMartyn pic.twitter.com/4X1qvxmIfj— Victoria Finan (@victoriafinan) May 22, 2018
People are also taking the opportunity to flood social media with pictures of bees, as they did in the immediate aftermath of the attack, which represent the city's "worker bees" and became a symbol of city-wide solidarity.