People have lined the streets of Clones, in County Monaghan, to form a guard of honour for one of the two teenagers killed on their way to an end-of-year school dance.

Kiea McCann, 17, and Dlava Mohamed, 16, died near the Irish border, after a car which was carrying five people left the N54 road and hit a tree, Gardaí (Irish police) said.

In their death notices, their families said they were best friends.

On Tuesday night, mourners gathered on Monaghan Street and at The Diamond, as a mark of support for the family, as Kiea’s body was brought home.

Death notices for both girls described the deaths as untimely and said they would be sorely missed by those who knew them.

BBC News NI understands Dlava’s family moved to Ireland from Syria about seven years ago.

Supt Patrick O’Connell described the incident as “particularly traumatic” for all involved.

Speaking outside Clones Garda Station on Tuesday evening, Supt O’Connell said the families were at the scene on Monday night and were “suffering from shock and trauma”.

“Having attended the scene last night, it was particularly harrowing, particularly the chaos that emanates when such an incident happens,” he added.

“The fire service, the ambulance service were particularly brilliant. Without them we wouldn’t have been able to manage this incident.”

Five people were travelling in the car when it crashed on its way to a debutants’ ball – a dinner-dance event for school-leavers – at about 18:45 local time.

The vehicle was driven by a 60-year-old man who was taken to the Royal Victoria Hospital in Belfast where he remains in a critical condition.

An 18-year-old woman, believed to be Dlava’s sister, was taken to Cavan General Hospital where she is in a critical but stable condition.

An 18-year-old man continues to be treated at the same hospital for non-life-threatening injuries.

The main road between Clones and Smithborough has reopened after the vehicle was removed from the scene earlier on Tuesday.

Gardaí (Irish police) have appealed to witnesses or those with dash-cam footage to contact them.

Their focus at this stage is on supporting the families and community, Supt O’Connell added.

A senior investigating officer has been appointed and a number of other previous crashes on the same road will help to form part of the investigation.

Earlier, the principal of Largy College in Clones said the school’s staff and pupils were in “deep shock” over the girls’ deaths.

The end-of-year “debs” ball was organised by the secondary school, which has about 450 pupils.

Principal Sharon Magennis said: “It is with profound sadness and grief that we have learned about the devastating accident that resulted in the untimely and tragic loss of two cherished members of our school community.

“We extend our deepest sympathies to the families and friends who have tragically lost loved ones.”

She said the school’s priority was the welfare of its students, their parents and teaching staff.

“The Largy College critical incident team has met to coordinate a response and to enact the critical incident plan,” added Ms Magennis.

The college opened on Monday night to provide support for the schoolmates of the victims, according to Monaghan councillor Pat Treanor.

“It’s an absolute horror that’s unfolding here from last night,” he said.

“All these young people were gathering on the Diamond in Clones to meet and head to the debs, with all the joy and the photographs and parents dropping them off.

“From that to about an hour later, hearing about this terrible tragedy, people are shocked and I suppose trying to come to terms with it.”

Monaghan councillor Richard Truell said people were reeling from the tragedy.

“The news has shocked County Monaghan and the surrounding counties,” he told BBC News NI.

“The close community is just numb, people have no words.”

Mr Truell said the ball was cancelled in the aftermath of the crash and a youth centre was set up in Clones to provide support to the students.

“The families have to pick up the pieces now unfortunately and their friends are going to surely miss them,” he said.

“It’s a tight-knit community and they are going to have to rally around the families affected.”

‘A dark cloud over the town’

At the scene: BBC Evening Extra reporter Julie McCullough

“It’s like a dark cloud is over the town” – that’s what one man told me in the Diamond area of Clones today.

Only yesterday evening they had been gathering here to get photos taken before their big night out.

No one could have imagined the news that was to come through a short time later – that two of their school friends had been killed in a crash while making their way to the venue.

‘Maturity and empathy’

The debs event was hosted by the Westenra Arms Hotel in Monaghan town.

Its manager Gregory McGonigle told BBC News NI that students had gathered in the hotel for their meal when they heard the news of the crash.

He said the event was then called off and buses were arranged to take the students back to their school, to be met by their parents and teachers.

The hotel posted a message of sympathy on its Facebook page.

“Our thoughts are also with all the community associated with Largy College and to all students who displayed great maturity and empathy upon hearing the tragic news,” it said.