Ammanford school stabbing: A timeline of events as update issued on injured teachers and pupil
Here's a summary of all events since news broke Wednesday morning.
WEDNESDAY
11:20 - The incident happens and pupils are placed under lockdown in classrooms. Dyfed Powys Police are contacted and emergency services arrive shortly after.
13:20 - Police issue an update confirming three people have been injured and receiving treatment.
They confirm one person has been arrested and they are not looking for anyone else. Emergency services remain at the scene.
By this time parents and families had begun gathering at the school gates.
15:20 - Pupils are released from school.
Celyn and Megan were not in the school during lockdown.
16:53 - Police issue a second update confirming the three people injured are two teachers and one teenage pupil.
They say they have all been taken to hospital with stab wounds and family has been informed.
They confirm that a teenage girl has been arrested on suspicion of attempted murder and remains in police custody.
In the statement they say that the "incident has concluded" and they are working with the school and other agencies "to ensure appropriate support is available to all involved.
“This was a very distressing incident and our thoughts are with the victims, their family and everyone impacted by what has happened.
“I am aware that there is footage of the incident currently circulating on social media and would ask that this is removed to avoid contempt of court and distress to those affected.
“I would also ask that people do not speculate while there is a police investigation ongoing.
"Local people will see more police in the area over the coming days as the investigation continues.”
17:50 - Police hold a press conference where they confirm a knife has been recovered.
Late Wednesday Evening - Ysgol Dyffryn Aman issue a statement on their website saying "Today has been a very difficult day.
"It goes without saying that my thoughts are with the three individuals and their families, who have been affected by today's incident.
"I wish to commend all staff and pupils for their calm and mature response during today's lockdown.
"We are proud to have witnessed pupils embodying the school's core values while supporting their peers and staff.
"In the immediate aftermath of the incident, our priority was to ensure the security of pupils and staff whilst managing the situation and communicating with those directly impacted."
THURSDAY
From 08:00 - Cefin Campbell, the MS for Mid and West Wales, who attended the school, appears on BBC Radio Wales and says his brother is a longstanding teacher at the school, and restrained a pupil during the incident.
Around 09:00 - Police confirm a teenage boy was arrested overnight, following threats involving a firearm.
Police recovered a BB gun from an address in the area. This is not yet connected to events at Ysgol Dyffryn Aman.
12:14 - Police issue an update saying all three victims have been discharged from hospital and the teenage girl remains in custody.
Officer's presence continues at the school as they "look for evidence to assist the investigation."
By this time ITV Wales understands the two teachers can be named as Fiona Elias the Assistant Head and Liz Hopkin a special needs teacher.
14:36 - Police confirm that a teenager from Cross Hands remains in custody on suspicion of making threats which had references to the incident at Ysgol Dyffryn Aman.
They say he was arrested following reports about threatening messages being sent on social media, which led to his arrest during the early hours of Thursday morning.
Superintendent Ross Evans said “while this investigation is being run separately to our enquiries into the major incident at Ysgol Dyffryn Amman yesterday, our officers will be seeking to establish both the credibility of the threats, and whether there was any connection between the alleged offences."
16:10 Carmarthenshire Council say the school will remain closed to pupils on Friday although teachers and staff will return. They hope pupils will be able to return on monday.
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