A fifth man has been arrested as part of the investigation into the shooting of a senior PSNI officer in Co Tyrone earlier this week.
Detective Chief Inspector John Caldwell was shot a number of times by two gunmen as he was putting footballs in the boot of his car with his young son at a sports complex on Killyclogher Road in Omagh.
Detectives investigating the shooting made the latest arrest this evening.
The fifth man, aged 43, was arrested in the Stewartstown area under the Terrorism Act and is currently being questioned by detectives in Musgrave Serious Crime Suite.
Four other men - aged 22, 38, 45, and 47 - were arrested previously and remain in custody.
The PSNI is treating the shooting of Detective Chief Inspector Caldwell as "terrorist-related", adding that their primary line of enquiry is now the New IRA.
In a statement this afternoon, Assistant Chief Constable for Crime Department Mark McEwan renewed an appeal for information.
Earlier, the the PSNI Chief Constable said Detective Chief Inspector Caldwell remains "critically ill and heavily sedated".
Speaking at a press conference, Simon Byrne said he understands "how important it is" that they were joined "in an act of unity" by all political parties across Northern Ireland.
He said they are aware of the "sheer sense of outrage at this pointless and senseless attack".
Giving an update on his condition, Chief Constable Byrne said his colleague remains critically ill and heavily sedated in hospital following surgery on his wounds.
"Last night I had the chance to speak to John's wife and son," he told reporters.
"They are clearly heavily affected by what they have gone through but want to pass on their thanks, both to people that rendered first aid and care at the scene, and also in terms of the outpouring of support across the community in relation to this awful outrage.
"We've had a chance to talk to political leaders about the pace and context of this investigation, what it means for policing and what we sense will happen in the next few days.
"We echo our thanks because it has rippled through the organisation about how important it is that we're joined by the political leaders today at this unique time to show that we stand together and call out this outrage for what it is."
Also speaking at the press conference, Sinn Féin deputy leader Michelle O'Neill said it was important in moments like this to stand united.
"And we do stand here united as one voice in our condemnation against this horrific attack on a police officer," she said.
"I think that the most powerful message we as political leaders can do is stand with the police service and say this is not good enough. This is an attack on our community."
"We tell these people out there who try to undermine our peace that it will not work because we stand united"
DUP leader Jeffrey Donaldson said they stand with the police to ensure those responsible are brought to justice and do not dictate how Northern Ireland moves forward in the future.
"To the evil people who carried out this heinous attack, you are not the future of this place, we stand against you," Mr Donaldson said.
UUP leader Doug Beattie said the shooting was an attack on the Good Friday Agreement.
"We tell these people out there who try to undermine our peace that it will not work because we stand united," he said.
SDLP leader Colum Eastwood said those who carried out the shooting represent "nobody and will achieve nothing".
"They think they are at war with the British state but they are at war with the people of Ireland," he said.
"And from my perspective, that is a battle they will never, ever win."
The Alliance Party's Stephen Farry said all five political parties were standing shoulder to shoulder and are all "utterly united in rejecting terrorism".
Meanwhile, the PSNI has appealed for the public's help to catch the gunmen who shot Detective Chief Inspector Caldwell.
Police say two gunmen in dark clothing carried out the attack and fled the scene on foot before getting into a small dark car.
The car was later found abandoned and on fire at Racolpa Road in Omagh, a short distance from the scene.
Detectives are appealing for anyone who may have been in the vicinity of the sports complex where the shooting happened and witnessed it, to come forward.
They are also asking for anyone with dashcam footage, mobile footage, CCTV or still pictures to send it to them and have provided an online portal where it can be uploaded.
They say several vehicles in the complex carpark were struck by some of the rounds fired during the attack.
The dissident republican group the New IRA are the "primary focus" of the PSNI's attempted murder probe.
The attack has been condemned by political leaders across Ireland and the UK.
Mr Caldwell is a high-profile officer who has led a number of major investigations, including taking a leading role in the murder probe following the killing of Natalie McNally in Lurgan in December.
Trade unionists in Northern Ireland have organised a rally in Omagh tomorrow in protest at the attempted murder of Mr Caldwell. It is due to take place in the town centre at 11.30am.
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Additional reporting Conor Macauley
