Image copyright Facebook Image caption Laura MacIntyre (left) has been found seriously injured. Her friend Eilidh MacLeod (right) remains unaccounted for

One of two teenage girls from the Isle of Barra who was unaccounted for after the suicide bombing in Manchester has been found alive in hospital.

Fifteen-year-old Laura MacIntyre is said to be seriously injured. Her friend, 14-year-old Eilidh MacLeod remains unaccounted for.

Twenty-two people were killed and about 60 others were wounded in the explosion at Manchester's MEN arena.

The teenagers had not been seen since the attack on Monday night.

The explosion came as crowds were leaving a performance by US singer Ariana Grande at 22:35.

The girls, who are pupils at Castlebay Community School, were accompanied by family on their trip to Manchester.

Both girls' parents have flown to Manchester.

'Huge shock'

Angus MacNeil, the former Western Isles MP, who knows the families of both girls, said Laura's injuries would suggest she had not been far from the bomber.

He told the BBC: "Laura is in hospital. She's alive, she's in a serious condition. We are still very worried for her, of course, the whole island is worried.

"We are very worried for Eilidh MacLeod. Our hearts go out to both families. It's been a huge shock to everyone on the island."

He said he had been to see Laura's grandmother who he knew very well.

"There's just shock and disbelief," he said.

Image copyright European Photopress Agency Image caption Tributes were left in Manchester following the attack

Speaking about Laura, he said: "If we are guessing from her injuries, she wasn't far from the bomber."

He added that Laura was a great friend of his daughter.

"She's often round my house here," he said. "My daughter calls Laura's granny her granny. Eilidh is a good piper in the island. They are just both lovely girls.

"It's difficult for the community. People are trying to make sense of how this could happen - how you could leave a wee place like Barra and be caught up in this.

"It's very difficult to process and to understand and to find reasoning for it."

He also spoke about the impact on the close-knit community.

"If people here don't have children the age of Laura and Eilidh they will certainly know their families," he said. "They are feeling the pain of the families.

"This does seem a very different place to the world of international terrorism on the news."

Family anguish

First Minister Nicola Sturgeon is due to hold another meeting of the resilience committee after the UK threat level was raised to its highest "critical" level.

She said: "I have been briefed this evening by the National Security Adviser regarding the Joint Terrorism Analysis Centre's decision to increase the threat level from severe to critical, and to invoke Operation Temperer.

"The resilience committee will convene tonight to allow me to discuss with ministerial colleagues and Police Scotland the practical implications for Scotland and ensure that all appropriate actions are being taken.

"The public should not be unduly concerned but should remain vigilant.

"In the meantime, our thoughts remain with all those affected by this dreadful atrocity."

Speaking about the girls from Barra, Ms Sturgeon earlier told the Scottish Parliament: "It is hard for anyone of us to imagine the anguish their families are going through right now. They are in our thoughts."

Image copyright Peter Byrne Image caption Armed officers rushed to the scene on Monday night

Image copyright Getty Images

She added: "The Scottish government and Police Scotland will do all we possibly can to ensure they have all the support that they need."

Laura's father Michael MacIntyre earlier tweeted: "Please...please retweet. Looking for my daughter and her friend. Laura Macintyre and Eilidh Macleod #manchesterattack"

An appeal by Eilidh's aunt Margaret MacNeil has also been shared tens of thousands of times on Facebook. She said at 10:00 on Tuesday that there was still no news.

Western Isles Council - Comhairle nan Eilean Siar - earlier said it shared the concerns of the girls' families.

'Loud bang'

A spokesman for the comhairle said: "We are closely monitoring events around Eilidh and Laura.

"Our thoughts are with the families of the two girls."

The local authority said it was "mindful of the impact" on pupils and staff at Castlebay Community School and was providing "all necessary support".

Lauren Baxter, 20, from Glasgow, has told BBC Scotland of the scene inside the arena at the time of the attack.

She said: "There was a loud bang from the back of the arena.

"I thought it was seating had fallen or the stage had fallen down. That was how loud it was."

Ms Baxter then saw people running and screaming.

Image copyright Dave Thompson

She said: "There were thousands in the arena when this happened. People were running upstairs trying to get out."

Greater Manchester Police said the lone male attacker, who died in the blast, was carrying an improvised explosive device which he detonated.

Sixty ambulances attended the incident and those wounded are being treated at six hospitals around the city.

In the aftermath of the attack witnesses spoke about the fear and confusion that gripped those caught up in the events.

A man from Glasgow, who was at the concert with his 11-year-old daughter, told the BBC he was leaving the arena about 90 seconds after Ariana Grande came off the stage and was about two rows from the front when he heard a "big boom".

The father, Clark, said: "Then there was sheer panic. And then we had to get out. That's all we know, we got out after that and we came back up to the hotel because everybody was being told to leave as soon as possible."

He said: "There were bodies running everywhere. Kids screaming. Everybody ran right to the front and I had to shield Ashlyn against the railings instead of getting crushed - and there was little girls shielding in beside me as well, so I was trying to look after them as well.

"Then it started to calm down and everybody started to head back out after that."

His daughter Ashlyn said: "I just thought that Ariana Grande would be ashamed of people being hurt at her concert.

"I was a wee bit nervous about what was going to happen next but I wasn't freaked or anything. I was just calm and just wanted to go back to my hotel because I was really sad and stuff."

Kerry Stewart and Terri Robertson from Aberdeen were at the concert and were making their way to the exit when the blast happened.

Media playback is unsupported on your device Media caption Kerry and Terri say there was confusion after the explosion

They told BBC Radio Five Live: "We came out of the toilet, about to go to the exit, and there were hundreds of people started running towards us.

"When we turned round there were people running from the other direction towards us and we got pushed into a room with heaps of kegs of beer. Everyone was fighting each other to try and get out an exit but it was a dead end.

"It wasn't a loud noise that startled us. It was just like a noise that you would have thought was part of the concert, until everybody started running.

"And then someone shouted 'there's the fire exit, run for safety' and we just started running."