SYDNEY extremists are believed to have recruited the teenage gunman to carry out Friday’s attack because they believed they were under too much surveillance to do it themselves.

According to Fairfax media, schoolboy Farhad Jabar, 15, met with several men at Parramatta mosque hours before he shot and killed police accountant Curtis Cheng.

It is believed there is CCTV which shows the year 10 student meeting with the men at the mosque.

One of the major lines of inquiries into last week’s terror attack outside NSW Police headquarters has been how the 15-year-old managed to acquire the weapon he used to shoot Mr Cheng.

Earlier today, The Daily Telegraph reported a Middle Eastern crime gang may have supplied the gun to the boy in the lead up to the shooting.

As part of the ongoing investigation, counterterrorism raids were carried out across Sydney on Wednesday morning.

Four men and a teenage boy were arrested as a result.

Two of those men, both aged 22, were released without charge late Wednesday afternoon.

A New South Wales police spokeswoman said the men were released following the expiration of the detention period specified in the warrant.

“A significant investigation remains ongoing,” she added.

A 16-year-old schoolmate of teen gunman Farhad Jabar and the schoolmate’s 18-year-old brother are believed to still be in custody.

It was also revealed that at least three of the men arrested had been targeted in terror raids last year over a plot to behead a member of the public.

And one of the homes in Merrylands that was searched had been targeted several months ago in relation to an alleged plot to stage a drive-by shooting, The Daily Telegraph reported.

Following the raid on the Lockwood Street house two men were taken away in handcuffs.

Addressing media earlier today in Sydney, Deputy Police Commissioner Catherine Burn confirmed some of those arrested had previously been targeted in counter-terror operations.

“We know some of the people we are now interested in are people that have come under notice previously,” Ms Burn said.

Last September, police carried out sweeping pre-dawn counterterrorism raids in western Sydney as part of Operation Appleby, uncovering a terror cell which planned to publicly execute a person in Sydney.

It is believed one of the houses targeted today was that of Omarjan Azari, who was charged following last year’s Appleby raids with conspiring with members of the terrorist group Islamic State to kill a person at random in Sydney and film the attack, The Australian reported.

All those arrested today will now be questioned over their involvement with Friday’s attack and in some cases, links with Islamic State.

Earlier today, Deputy Police Commissioner Catherine Burn confirmed some of the people targeted in Wednesday’s raids had attended Parramatta mosque. She said police were investigating the source of the firearm, and confirmed investigators suspected Jabar had not acted alone.

Ms Burn said today’s operation was “a clear indication of our determination to actually find out who murdered Curtis Cheng and to take all necessary action that we possibly can”.

“It’s a very, very serious concern that in the heart of our community there is attack planning that is underway and that may have led to what we saw on Friday," she said.

The raids began just after 6am on Wednesday when dozens of marked police cars and specialist vans left Merrylands Police station. Armed officers raided four houses in Guildford, Wentworthville, Merrylands and Marsfield early this morning.

A police spokesman confirmed the arrests were in relation to the fatal shooting of Mr Cheng.

Mr Cheng was executed as he left work on Friday at 4.30pm by teen terrorist Farhad Jabar.

This morning’s raids were co-ordinated with the counterterrorism squad and homicide squad.

More than 200 armed NSW officers as well as the Australian Federal Police arrested the five men aged between 16 and 24.

Two men aged 16 and 18 have been arrested at Wentworthville, two men aged 22 and 24 have been arrested at Merrylands and a 22-year-old arrested at is Marsfield home.

Ms Burn said Farhad was not on the police radar and “not somebody we would have assessed as a threat”.

“I’m not going to speculate on the motives of either the 15-year-old or anybody else who might be connected with this,” she said.

“It’s difficult because we don’t really know the motivation of the 15-year-old, however, we are dealing with this as — what we are investigating is a terrorism offence so what we would suggest and we suspect is that there was some influence, whether it was ideologically, religious or politically motivated, that determined and influenced the 15-year-old to go and commit this horrendous act of violence.”

WENTWORTHVILLE RAID

Police have confirmed raids have been executed at Bursill Street, Guilford; Lane Street, Wentworthville; Lockwood Street, Merrylands; and Booth Street, Marsfield.

A huge section of Lane Street, Wentworthville, has been blocked off where heavily armed counterterrorism police have performed a raid on a unit block.

Two men aged 22 and 24 were arrested and led away from the street early this morning.

The Daily Telegraph can confirm the raid targeted the family home of a man who had been investigated by police for possible Islamic State links.

He was also targeted in last year’s terror raids and was one of the men arrested this morning.

The men detained this morning are believed to be linked to extremist groups operating in Australia and abroad.

It is believed at least one of the men is an associate of terror suspect Omarjan Azari who was arrested in dawn raids last year over his alleged involvement in a plot to behead a member of the public.

A teenager, wearing nothing but football shorts, has been also arrested at the scene, and is the brother of one of the arrested men.

The shirtless man made obscene gestures at The Daily Telegraph and mouthed profanities.

A massive number of Public Order and Riot Squad officers remain at the scene and are guarding a number of locations with high-powered weapons.

Concerned neighbours, meanwhile, are piling on to the street.

Officers from the joint counter terrorism task force continue to swarm the area as detectives scour the unit block where two men were arrested.

“It is very worrying,” said one neighbour.

Another resident thought the chaos this morning was a result of him calling the police with a noise complaint about dogs barking at the address.

MARSFIELD RAID

Police have raided the same house in Sydney’s north west twice within about 12 months for terrorism investigations.

They arrested a 22-year-old man from a duplex on Booth St, Marsfield.

Heavily-armed officers converged on the house about 5am.

They have remained at the scene and are searching the house, garage and a Toyota Corolla parked in the driveway.

Derek Archer, 52, lives opposite the house which was raided and woke up to the noise of the police raid.

“I just woke up to some large shouting similar to 12 months ago, just ‘get down, get down’,” he said.

“We didn’t open the door this time or anything like that, just had a look out the window.”

MERRYLANDS RAID

A woman who returned home in the middle of the Merrylands raid lashed out at reporters in the street.

The woman was trying to enter the home being guarded by police when she struck out at a camera and tried to tear the microphone from a reporter’s hand.

One of the arrested men’s mothers has also been taken into custody after she had to be restrained from attacking police, Seven News reports.

There were also reports of eggs being thrown from a house on Lockwood Street at media who were reporting from the street.

Most missed, but a photographer and a cameraman were caught in the crossfire, while a TV journalist managed to duck during a live cross, Fairfax reported.

I'm glad the "egg bandits" can't aim. Would have really hurt @Natalia_Cooper9 if it had hit her. Fools. pic.twitter.com/Ucla09KKB3 — Tiffany Wertheimer (@TiffWertheimer9) October 6, 2015

Sydney terror raids - Family lashes out at media and Police Police conducting raids on homes in the Sydney including the suburb of Merrylands where home owners are upset and have lashed out at media. Courtesy: Sunrise

GUILDFORD RAIDS

Counter-terrorism detectives have removed a number of large bags of evidence from the Guildford family home of terror suspect Omarjan Azari.

The evidence was seized and labelled with Australian Federal Police insignia and taken away for examination.

Plain clothed detectives and NSW Police officers continue to swarm through the home as part of the operation in response to the callous shooting of Curtis Cheng in front of NSW Police headquarters last Friday.

At least one of the men arrested in this morning’s terror raids is a known associate of Azari’s and visited his home in the aftermath of last year’s dawn raids — known as Operation Appleby.

TEENAGER CHARGED TUESDAY

The arrested men have been linked to Friday’s terror attack and the dawn operation follows the raid of the Guilford home of a 17-year-old schoolboy who was yesterday charged over supporting Jabar’s attack.

Police have stressed yesterday’s arrest and today’s raids are not related.

At about 5pm yesterday officers seized laptops and other items for examination from the boy’s home.

The teenager, who cannot be named for legal reasons, was arrested on his way to Arthur Phillip school in Parramatta — the same school the 15-year-old police shooter attended.

Police allege the teenager threatened and intimidated police as they questioned him over a series of threatening social media posts.

The 17-year-old is charged with assaulting and intimidating police, two counts of resisting arrest and using a carriage service to harass and offend.

Though the Facebook account used to issue threats has been deactivated since the teenager’s arrest, posts seen by news.com.au contained threats to police and praise of Friday’s terror attack.

“Serves you right lil piggies hope you get shot,” one post read.

“Bahahja f**k you motherf**ker Yallah merryland police station is next hope they all burn in hell.”

Another social media account containing threats to police under the charged boy’s name is still active.

AFP has stressed that today’s arrests are not related to the arrest of the juvenile in Parramatta yesterday.

The suburbs targeted in this morning’s raids have previously been the focus of counter-terror operations.

In September last year homes in Guilford, Merrylands, Wentworthville were targeted by counter-terror police and revealed a plot to behead a member of the public in the country’s largest ever counter-terror operation.

A series of raids in Marsfield in December saw two men charged with terror offences.

Some police have arrived back at Merrylands PS to debrief following this morning's terror raids. pic.twitter.com/lKTU5OdY5J — Mathew Woolfrey (@mattywoolfrey) October 6, 2015

‘WE NEED TO BE VIGILANT’

Justice Minister Michael Keenan, who is also the Minister assisting the Prime Minister on Counter Terrorism confirmed details of this morning’s arrests and their links to the fatal shooting of police worker Curtis Cheng.

Mr Keenan told ABC radio it was “very concerning” that there had been praise on social media for the 15-year-old who had carried out the attack.

While admitting it was concerning young boys were being radicalised, the minister defended the government’s efforts to ensure young people aren’t influenced by terror forces.

“Australia’s program is world leading and we are doing an enormous amount to make sure we’re equipping communities,” he said.

“It’s not one size fits all ... we are working to divert people if they are falling under the spell of ISIL in the Middle East. We must remember that they are very sophisticated at this, they are sending over 1000 social media messages a day.”

Mr Keenan was careful not to implicate the Parramatta school or mosque teen terrorist Farhad Jabar and others arrested have been linked to.

“We need to be vigilant to make sure people in the community and institutions are getting the right messages. We do need to be vigilant, we can’t have our young people getting these terrible poisonous messages,” he said.

“We’re particularly concerned about the online environment but we must make sure that institutions such as schools or religious institutions are also preaching the right messages and giving the right messages to young people.”

Deputy Commissioner Burn also called for calm and vigilance.

“While the events of last Friday are disturbing, we have to be better than those who want to disrupt our lives,” she said.

“It’s important that we get on with our lives. But we have to be vigilant, be aware and be ready to make a call if you see or hear anything suspicious.”