• See more Daily Mail on Google - save us as a Preferred Source

A trainee barrister who was allegedly caught driving a car bomb towards Northern Ireland in a suspected New IRA operation spent time in Syria, her lawyer said.

Isobella Perrie Sullivan, 25, was arrested after Irish police said they made an 'extremely significant seizure' of a device on Wednesday.

The force said the device, which was made from military-grade plastic, could have caused significant damage.

It is understood to be the most sophisticated bomb seized by police since the Troubles.

A man in his 40s was also arrested in the major investigation, with Irish news outlets reporting that the man was a suspected member of the New IRA's Dublin branch.

In an intelligence-led swoop, the Garda's Special Detective Unit stopped the vehicle in transit near the Irish border on Wednesday afternoon on the N2 south of Carrickmacross, County Monaghan.

Sullivan, from Clane in Co Kildare, was granted bail on Friday after appearing before a special sitting of Trim District Court in Co Meath charged with possession of explosives.

It has now emerged her solicitor Mr Gavin Booth told the court she was a previous member of a 'political group' and had spent some time in Syria.

Isobella Perrie Sullivan, 25, was arrested after Irish police said they made an 'extremely significant seizure' of a device on Wednesday

Sullivan leaves the after appearing before a special sitting of Trim District Court in Co Meath charged with possession of explosives

Mr Booth, however, said Sullivan had stepped away from politics as she focused on her studies as a barrister.

Sullivan, reportedly known as Perrie, was a student at ATU Donegal in Letterkenny and graduated last year with a law degree.

Mr Booth said his client had been asked to take a bag to the north and was not aware of its contents. He added Sullivan, who lives with her father, had been 'manipulated'.

He said her parents are 'devastated' and can't comprehend this week's events. He added, if she was granted bail, they would keep her on a 'tight rein and ensure she abides by all conditions'.

Judge Raymond Finnegan granted Sullivan bail on Friday provided she obtained a €15,000 (£12,800) independent surety.

She, who was wearing a pink White Fox Boutique hoodie at the time, was also ordered to surrender her passport and keep to a strict curfew.

The male suspect remained at a Garda station in the Dublin area on Friday night

Garda Commissioner Justin Kelly confirmed details of the operation as he spoke to media at a Garda graduation event in Co Tipperary on Friday.

Garda Commissioner Justin Kelly spoke to reporters on Friday in Templemore, Co Tipperary

'To be clear, what we found was an extremely significant seizure,' he said. 'So this was an explosive device.'

Commissioner Kelly added: 'Any seizure of this nature is really concerning.

'However, we certainly know that there are a small minority of dissident republicans who did not agree with the Good Friday Agreement, they did not put weapons and explosives (out of use), they didn't, you know, go through with the proper process in relation to decommissioning. So that is something that we continue to deal with.

'There's a small minority of these individuals, I would describe them as radicalised republicans, and this is a threat that we're going to continue to face for some time in An Garda Síochána.

'We work very closely with our colleagues in PSNI (Police Service of Northern Ireland) and the intelligence services in the UK to deal with this threat. But I want to commend the members of An Garda Síochána who are involved in this operation.'

Mr Kelly also indicated that the bomb was already constructed when it was seized.

'Unfortunately for operational reasons, I can't go into the exact detail of the device,' he said. 'But what I will say certainly it was a significant explosive device. So certainly not just the seizure of components or pieces.

'This was an explosive device and it would have or could have potentially caused significant damage.'

The commissioner confirmed the operation relied on intelligence. 'Obviously, this was not a random stop,' he said.

'This is an intelligence-led operation. But, naturally, I can't go into a lot of that in public.'

Ireland's Minister for Justice Jim O'Callaghan described the seizure as 'very worrying'.

PSNI Assistant Chief Constable Davy Beck said police on both sides of the Irish border shared a 'joint commitment' to tackle the dissident republican terror threat.

Carrickmacross is about six miles (10km) from the border between the Republic of Ireland and Northern Ireland.

Sporadic attacks by militant groups, often attempted car bombings, continue in Northern Ireland almost three decades since a peace deal largely ended sectarian violence.