LONDON: Online reaction to the suspected terror attack on a pop concert that killed at least 19 people has been swift.

Singer Ariana Grande, who had just finished performing in Manchester, northern England, when the blast took place, tweeted that she was "broken" by the attack.

"From the bottom of my heart, I am so so sorry. I don't have words," the 23-year-old wrote on her verified @ArianaGrande account, which has more than 45 million followers.

As politicians from across the spectrum condemned the attack on Twitter, locals in Manchester also used social media to offer up accomodation and advice to those caught up in the chaos.

US rapper Nicki Minaj (@NICKIMINAJ), who collaborated with Grande on recent hits "Bang Bang" and "Side to Side" tweeted: "My heart hurts for my sister, Ariana & every family affected by this tragic event in the U.K. Innocent lives lost. I'm so sorry to hear this."

US pop princess Taylor Swift (@taylorswift13), a friend of Grande, tweeted: "My thoughts, prayers and tears for all those affected by the Manchester tragedy tonight. I'm sending all my love."

Katy Perry (@katyperry), also a friend of Grande, tweeted: "Broken hearted for the families tonight. Broken hearted for Ari. Broken hearted for the state of this world."

Up and coming American popstar Sabrina Carpenter (@SabrinaAnnLynn), who recently played in the northern English city with British pop rockers The Vamps, expressed her shock. "Just played Manchester.. crazy.. really don't have words. I'm so sorry. should be a safe place. :( Thinking of all those affected," she tweeted.

"Tearing up imagining innocent concert goers losing their lives," added US popstar Demi Lovato (@ddlovato). "Praying for everyone and all". 

Grande's manager Scooter Braun, who also represents Justin Bieber, published a longer statement through his Twitter account (@scooterbraun).

"We mourn the lives of children and loved ones taken by this cowardly act," the sombre black and white picture statement read. "We ask all of you to hold the victims, their families, and all those affected in your hearts and prayers."

Locals offer up beds

Politicians also took to social media to condemn the attack and send their condolences.

Jeremy Corbyn (@jeremycorbyn), leader of Britain's main opposition Labour Party tweeted: "Terrible incident in Manchester. My thoughts are with all those affected and our brilliant emergency services."

Andy Burnham, the newly elected Mayor of Manchester (@MayorofGM), added: "My heart goes out to families who have lost loved ones, my admiration to our brave emergency services. A terrible night for our great city"

London Mayor Sadiq Khan (@SadiqKhan) said: "London stands with Manchester - our thoughts are with all those killed and injured tonight and our brave emergency services."

Nigel Farage (@Nigel_Farage), who led the anti-immigration UK Independence Party through Britain's divisive vote to leave the European Union tweeted: "Horrified at the bombing in Manchester. No doubt we will find out who the perpetrator is soon. My thoughts are with those affected."

Across Manchester itself locals used Twitter to say their doors were open to those needing a bed for the night or simply a cup of tea, many using the hashtag #roomformanchester.

-AFP