threats of terror attacks on at least four Australian churches prompted police to protect thousands of Coptic Christians during Christmas Eve services.
Police on Thursday surrounded the Coptic Orthodox churches in Sydney after a bomb blast killed 21 people during a New Year's Eve Coptic church service in Alexandria, Egypt.
Coptic Churches around the world are also on high alert as their Christmas Eve services are scheduled for Friday (Australian time).
On Thursday night in Sydney, bomb searches and police helicopters were part of the security measures that soured Christmas Eve celebrations.
Some church officials are worried that an attack may eventuate when least expected on any on of their churches, monasteries or schools in Australia.
A police detail searched St Antonious and St Paul parish in Guildford, in Sydney's west, on Thursday afternoon prior to its 7pm Christmas Eve services, a church official told AAP.
Up to 700 parishioners were estimated to be in attendance.
During the service, teams of officers surrounded the area while helicopters with spotlights searched the local suburb.
'There were threats to our church - three or four churches in the (Sydney) Coptic church,' said the man who asked not to be identified.
He said NSW Police contacted the church this week to say the Guildford site and three others in Sydney had been the target of a terrorist threat.
Archangel and St Bishoy at Mt Druitt, in Sydney's west, St Demiana and St Athanasius at Punchbowl, in Sydney's southwest and St Mary and St Merkorious, at Rhodes, were understood to be on the threat list.
A woman witnessed a police operation in her neighbourhood at Arncliffe, where St Mark Coptic Church is located in Sydney's south.
'The police helicopter is sweeping the suburb with this massive spotlight,' the woman told AAP.
All of the churches cancelled their traditional dinners that would normally happen after Christmas Eve services.
The spokesman said Thursday's threat, which resulted in no reported incidents, could have been a diversion.
'They want you to focus on the area that they're not going to be touching,' he said.
'And even though the threat was for Christmas Eve, they might do it on a normal Sunday. That's how they work.'
Police issued a statement to AAP following Thursday's operations.
'The NSW Police Force is closely monitoring international developments in the wake of the attack on the Coptic community in Egypt,' the statement read.
'Police have met with local Coptic leaders and are currently working with them to allay any fears within that community.'
Peter Mikhail attended the Guildford service and said the threats soured the service and have put fear into the congregation.
'It was not a nice way to be celebrating Christmas here in a country where you're supposed to be safe,' Mr Mikhail told AAP.
He said the traditionally long mass but had to be cut short at police request and people were dispersed immediately.
'We went to church today feeling quite apprehensive thinking oh my God' what if something does take place,' Mr Mikhail said.
'I'm worried about my wife, I'm worried about my kids.'
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