POLICE have said that it is ‘very clear’ a network is being investigated following the Manchester Arena bombing.

Greater Manchester Chief Constable Ian Hopkins made the comments at a media briefing this afternoon.

When asked whether police were still looking for the bomb maker, he said: “I think it is very clear that it is a network we are investigating.”

Mr Hopkins also confirmed that one of the 22 people killed in the blast was a serving police officer who was off duty at the time.

He added that police are confident they have spoken to all the immediate families of those who died in the attack and are being supported by specially trained officers.

However post mortems are due to take between four to five days so police will not be formally identifying anyone at this stage.

Mr Hopkins also confirmed that four people remain in custody following arrests overnight and a raid was carried out an address at a town centre property today where police gained entry by using a controlled explosion.

Raids have also been carried out in south Manchester.

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The chief constable also commented on the increase in the number of armed officers on the streets of Greater Manchester and whether armed forces will be deployed in the area.

He said: “People will have seen a significant increase in the number of armed officers in Greater Manchester. We have been supported by forces in the North West and beyond in order to do this and this all forms part of our tried and tested plan for a major terrorist incident.

“With the threat level being increased to critical you will be aware that military are supporting policing across the country. This is about using the military across sites in London and elsewhere to free up armed police officers to support police forces.

“There are no military personnel patrolling Manchester but we are therefore able to receive additional armed policing support because of this plan. We are using this to help in our efforts enable the Manchester Games and Manchester 10k to go ahead.

“We are working with event organisers and Manchester City Council to review and enhance our safety and security.”