An explosion at Manchester Arena has left 19 people dead and 59 injured.
Downing Street have said an emergency Cobra meeting will take place at 9am today.
Here's what we know so far:
If you're concerned about any friends or relatives then contact the emergency helpline: 0161 856 9400
Good Morning Britain has been nominated for a TV Choice Award in the Best Daytime Show category - and with our heated debates and heart-warming moments, it's no surprise!
If you love GMB help us get to the next level by voting by 2nd June.
Is it time to clamp down on our junk food habits?
Experts say that buses and trains should ban burgers to tackle obesity and claim it could save the NHS billions of pounds each year.
Researchers warn guzzling on the go is making Brits fat - and tempting others to be unhealthy.
Theresa May faces controversy over her social care reforms. A poll for Good Morning Britain shows the Tory's lead over Labour has halved. Also, the SNP launch their manifesto in Edinburgh on Tuesday morning at 11am at the EICC.
EU countries meet in Brussels today to try to sort out how and when Brexit negotiations will begin.
US President Donald Trump has urged Muslim countries to take the lead in combating radicalisation during a major speech in Saudi Arabia. Today he flies on to Israel.
Buses and trains should ban burgers to beat obesity, experts say. They want radical new rules stopping people eating junk food on all public transport. Obesity researchers warn guzzling on the go is making Brits fat - and tempting others to be unhealthy.
He's one of TVs most famous stars and he's hosting on one of the world's most famous stages! Bradley Walsh talks about Tonight At The London Palladium and outselling Zayn in the charts.
Have you opened a pack of snacks and been disappointed by the small amount of contents?
Hundreds of viewers have got in touch because they opened the packaging of items bought on their weekly shop and found a lot of empty space.
I don’t like going out because I’m scared of what I’m going to go out to
One of the victims of the Rochdale sexual abuse scandal has spoken to Good Morning Britain about how she was groomed, abused and subsequently "ignored" when she reported it.
'Lily, 22, appeared in the studio anonymously to tell us of how she was 15 when she was abused by older men in Rochdale. Her interview follows BBC drama Three Girls, which revealed how badly the victims of the abuse were treated not only by their abusers, but by the police and court system too.
On how she first became involved in the abuse, Lily explained how after the death of her parents she was living in foster care and spent her days walking the streets.
Tony Blair never did a debate, Margaret Thatcher never did a debate
Earlier David Davis has defended Theresa May’s decision to not take part in last night’s ITV Leaders' Debate saying Tony Blair and Margaret Thatcher never took part in a debate either.
The absent Conservative leader came under attack from the other political party members during the fiery debate.
When David was pressed about his Brexit plans he told us: "My aim and my expectation is that we’re going to get a free trade agreement - we're going to get a decent agreement with them".
Watch the full interview above.
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Five of Britain's party political leaders clashed at yesterday's ITV Leaders' Debate with an absent Theresa May and Jeremy Corbyn. Liberal Democrat leader Tim Farron, SNP leader Nicola Sturgeon, Ukip leader Paul Nuttall, Plaid Cymru leader Leanne Wood and Green co-leader Caroline Lucas all met at the battle field to discuss the Brexit deal and NHS funding and much more.
US President pays visit in what is his first foreign travel since taking office. As well as meeting King Salman, President Trump is set to meet with other Gulf leaders while there. He then heads to Israel, and then Italy. Trump is set to arrive today at an unspecified time. The official itinerary for his visit organised by Saudi officials will begin on Saturday 20th and continue on Sunday 21st.
Hundreds of viewers have got in touch because they opened the packaging of items bought on their weekly shop and found a lot of empty space. We'll discuss this more during the show.