We have set up two dedicated phone numbers for anyone with concerns relating to this incident.
Telephone Freephone 0800 092 0410 or 020 7158 0124 if you cannot dial Freephone numbers, or if you are calling from abroad.
The helpline is staffed by police and public health experts and is available from 8am to 8pm daily.
For those who may have information about this incident
Counter Terrorism Police are keen to hear from anyone who may have information that could assist with this investigation and would urge anyone who can help to call 0800 789 321.
Published on Thursday 5 July, 9.40am
Updated: Monday 16 July 15:30