Police officers have raided the family home of a teenager killed in Syria in search of “extremist material”.
His father Abubaker Deghayes said officers tried to knock down his front door in Arundel Drive East in Saltdean at 7am.
He told how officers then started searching through mobile phones, computers and financial records.
Abubaker added he felt his family was being unfairly targeted by the police.
Sussex Police said they searched the four addresses after search warrants were issued under the Terrorism Act 2000 in connection with the reported death of Abdullah Deghayes in Syria.
The force said relevant material was being taken away for examination.
Abubaker Deghayes said: “They rang the bell at 7am in the morning and then started knocking down the door. It was very scary.
“They told me they were looking for anything of an extremist nature.
“We are being unfairly targeted.”
On the subject of his two sons, Amer and Jaffar, who are still in war-torn Syria he said: “I have had messages from them saying they are fine.
“They say yes they are coming back home but I don't know whether they are just saying 'yes father' to please me.”
Chief Superintendent Nev Kemp, Brighton and Hove Divisional Commander, said the searches were not in response to any immediate threat to local communities.
He added: "This is a necessary part of our continuing work to safeguard communities locally and nationally, including those who have links to Syria.
“We understand what a distressing time this is for the family and we do not want to cause further distress to them.
“It is an important, for strong operational reasons, that we carry out these searches as part of our ongoing enquiries into events in Syria. We are carrying out the searches as quickly and sensitively as possible.”
Asim Qureshi is director of research at CAGE, a War on Terror victims' advocacy group.
He said: 'This is yet another example of the criminalisation of those that are connected with the Syrian conflict in any way, even when there is no evidence of criminality.
“Despite their openness and transparency and their still mourning the loss of a much-loved son, the Deghayes family now have to go through the whole ordeal of being targeted like criminals.”
The Foreign and Commonwealth Office is advising the whole of Syria is unsafe and people should not travel there.
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