Alexandra Burke felt forced to hire more minders for a public appearance on Wednesday night after she was sent sick online death threats.

The singer announced she would be at the launch of her new lip gloss line, Lip Booms, at London Rose Club via her Twitter account hours before she was due to make the appearance.

But the star was left shocked and scared after she was bombarded with abusive tweets from haters, with one even threatening to hurl bricks at her when she showed up at the venue.

According to The Mirror, Alexandra's mum Melissa was so concerned she called the cops, and her management decided to draft in extra security as a precaution.

A source tells the paper: "Alex's mum was particularly upset by the horrible messages so she decided it was best to contact the police.

"They went down to the venue before the party started, and Alex had a team of security around with her all night to make sure that she stayed safe."

But the night seemingly went without a hitch, with the former X Factor champ insisting she had a great time at the event.

She wrote on her Twitter page: "Had an amazing time at my launch tonight! Thanks 2everyone who came out&supported me. Means so much. Tonight was unreal. I'm so happy!

"Tear in my eye. I'm proud of myself. For once I can actually say it... so much2those who have supported me all the way. My heart is yours..."

@alexandramusic
Alexandra Burke

Had an amazing time at my launch tonight! Thanks 2everyone who came out&supported me. Means so much. Tonight was unreal. I'm so happy!

April 12, 2012 12:46 am via Twitter for BlackBerry® Reply Retweet Favorite

@alexandramusic
Alexandra Burke

Tear in my eye. I'm proud of myself. For once I can actually say it... so much2those who have supported me all the way. My heart is yours...

April 12, 2012 1:29 am via Twitter for BlackBerry® Reply Retweet Favorite

CELEBS ON TWITTER

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• Alan Carr

  Twitter ID: AlanCarr Good, bad or mad? Definitely good. Chatty Man Alan is one of the most consistently funny celebs on our Twitter feed. And most importantly, he knows that less is more. Sample tweet: Companies - don't be sh***y then when i ring up to complain get all giggly and say is that THE Alan Carr. Be sh***y 24/7 please!! PA

• Calvin Harris

  Twitter ID: calvinharris Good, bad or mad? Good. The lanky Scottish dance music producer comes across more like a funny mate than a celeb - and always interacts with his followers. Sample tweet: Can somebody please think of a joke with the punchline 'because William Shatner' ? -been trying for last 2 hours + given up PA

• Charlie Sheen

  Twitter ID: charliesheen Good, bad or mad? Mad as a lorry. The winningest warlock in showbizland gained two million followers in a day or two when he joined - and hasn't disappointed with a series of inspired and deranged tweets. We think he's swapped crack for Twitter addiction. Sample tweet: the title of my book has finally been delivered thru vast and extensive Lunar channels. "Apocalypse Me" Warlock Latin for WINNING. c PA

• Cher Lloyd

  Twitter ID: CherLloyd Good, Bad or mad? Good. You might be surprised that we're fans of Cher, but she always keeps it real on her Twitter and has a nice sense of fun - even when teased about her gypsy heritage. Sample tweet: keep chuckin those gypsy comments in, i'll tarmac ya drive and trim ya hedges for ya if ya like? No shame in me :L PA

• Denise Van Outen

  Twitter ID: denise_vanouten Good, bad or mad? Good. She mostly tweets to ask for parenting advice or stoke her feud with Natalie Cassidy - but that's fine by us because we can tell she really loves Twitter. Sample tweet: the Karvol plug in is working wonders. I'm high as a kite! No blockages in this house tonight PA

• 50 Cent

  Twitter ID: 50cent Good, bad or mad? Very bad. When he first hit Twitter we thought he was hilarious, then we realised he wasn't really putting on the angry gangsta act - and that he's actually a bit of a dick. Sample tweet: ok no homo is officially banded from my time line. If you choose a alternative life style that's your business. Sh*t I'm a PIMP lol PA

• Gok Wan

  TwitterID: therealgokwan Good, bad or mad? Good. We like Gok because he's funny, self-depreciating and takes the time to answer his followers. Sample tweet: Why is it when you need a wee you always hit roadworks? My driver is getting nervous as I've just asked him if he has an empty bottle! X PA

• Jedward

  Twitter ID: planetjedward Good, bad or mad? Absolutely barking mad. We should really un-follow them because they spout such a huge amount of nonsense - but there's something strangely compelling about their ramblings. Sample tweet: We are taking over the world ha ha ha ha not really just holding it like a bubble and then we will burst it and make a stronger cool bubble PA

• Kanye West

  Twitter ID: kanyewest Good, bad or mad? All three. Sometimes he can be smart and funny, sometimes he can be a berk and sometimes we have no idea what he's on about. Sample tweet: Dude from Muse just gave a shout out to "His Beautiful Pregnant Girlfriend" sounds like a good album title! PA

• Katie Price

  Twitter ID: MissKatiePrice Good, bad or mad? Good. Yep, that's right - we said good. Why? Becuase Britain's most hated woman (trust us on that) is never afraid to pick up her iPhone and tweet a quick comeback when she's in the news. She keeps us in business. Sample tweet: Mmm in the jacuzzi chillaxing my legs and knee hurting haha then eating my roast dinner and getting my nails done haha x PA

• Kelly Osbourne

  Twitter ID: MissKellyO Good, bad or mad? We can't decide. We used to like her, but then she started sticking it to Dannii Minogue in defence of her hateful mother Sharon. And she seems to have got a bit dull since she got thin too. Sample tweet: over it! the toilet over flowed due to a mystery log rider so i spent the last 2 hours walking around my apt dry heaving! PA

• Kim Kardashian

  Twitter ID: KimKardashian Good, bad or mad? Good. We love Kim because she's so down to earth for someone you'd expect to be a bit up themselves. She just seems quite nice, and that counts for a lot with us. Sample tweet:< I just drove for the 1st time in NYC! Got a little scared driving over a bridge, I'm afraid of heights...but the tunnel was cool! PA

• Lily Allen

  Twitter ID: lilyroseallen Good, bad or mad? Good. Lily is another celeb who keeps it real on Twitter - using it in just the same way that us mere mortals do. Sample tweet: On police,camera,action,why are the police always addressing the drivers they pull over as 'mate' ? Seems patronising, and antagonistic. PA

• Liz Hurley

  Twitter ID: ElizabethHurley Good, bad or mad? Really good, surprisingly. We were expecting Liz to be all stuck up, but she's honest, open and funny on Twitter. Sample tweet: Who's guilty of reading cookery books in bed, particularly when dieting? Eyeing them now...Martha Stewart Cakes looks tempting. PA

• Louie Spence

  Twitter ID: louiespence Good, bad or mad? Good. He may be a shameless attention whore, but Louie's Twitter feed is just as entertaining as his outrageous TV appearances. We love the steady stream of snaps showing him with different celebs. Sample tweet: Going to buy myself a new Lycra cat suite I'm 1 of the judges on Let's dance this sat night you've got to make the effort,may b a backless 1 PA

• Paris Hilton

  Twitter ID: ParisHilton Good, bad or mad? Good or bad, we can't decide. OK, so most of her Twitter feed is filled with plugs for her TV shows or products - or thinly-veiled boasts about her hollow, consumerist existence - but somehow we wouldn't want her to be any other way. Sample tweet: Flying back home from the race. Love Helicopters, such incredible views of Vegas and beats the traffic :) PA

• Peaches Geldof

  Twitter ID: peaches_g Good, bad or mad? Good, but a bit mad too. Of course there's plenty to dislike about Peaches - she comes across like a pretentious student a lot of the time - but her obvious enthusiasm for Twitter and her complete lack of discretion have won us over. Sample tweet: Watching Take Me Out is like watching meat swinging sadly in an abattoir. PA

• Piers Morgan

  Twitter ID: piersmorgan Good, bad or mad? Bad. The hardest-working schmoozer in the business came to Twitter late, but has certainly madeup for it with a seemingly never-ending stream of tweets designed either to promote himself or ingratiate him with other celebs or sports stars. Sample tweet: Got to be one Brit celebrity who thinks he can beat me on followers, isn't there? Going to be very dull if they all keep rolling over. PA

• Russell Brand

  Twitter ID: rustyrockets Good, mad or bad: He used to be good, but he seems to have lost his Twitter mojo a bit since hooking up with Katy. That's unfair actually - it's since he got all Hollywood big time that he doesn't seem to put as much effort into his tweets. Sample tweet: Brazil! Happy Marde Gras! Britain! Happy pancake day. Who needs nude street festivals? Pass the lemon juice. PA

• Stephen Fry

  Twitter ID: stephenfry Good, bad or mad? Bad. Controversial as it may be, we'll admit that his tweets bore us senseless and we eventually had to un-follow him. It's like being trapped inside the head of a very self-absorbed stranger. Sample tweet: I first tweeted from a plane two years ago, also an internal US flight. Wonder when it'll come to international flights. PA

• Jonathan Ross

  Twitter ID: wossy Good, bad or mad? Good. Unlike when he's on the telly or radio, Wossy seems to know when enough is enough on Twitter - and he's genuinely funny as well. Sample tweet: Went to see Burlesque with my girls the other day. Cher has now had so much work done she can only talk Klingon.Top lip completely immobile. PA

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