Gardaí say they are liaising closely with the security and law enforcement agencies in the UK following the attack in Manchester and are providing every assistance to the Greater Manchester Police.

A garda liaison officer based in the UK is in direct contact with the police and intelligence services there to enable the sharing and assessment of relevant information and intelligence.

Gardaí also work through Europol and Interpol.

In a statement, An Garda Síochána stressed that Ireland is a safe and secure environment but while there is no specific information in relation to any threat to Ireland from international terrorism, it is not immune from such a threat.

The threat assessment level in Ireland at the moment is moderate, meaning an attack is possible but unlikely.

The threat level in the UK has been raised from severe to critical.

Gardaí said the threat-level in Ireland remains unchanged but is under constant review and that remains the case following the incident in Manchester.

They said all appropriate measures will be taken commensurate with the prevailing threat environment.

The Garda's CTI unit which is part of the Special Detective Unit is tasked with dealing with international terrorism. 

The Garda National Immigration Bureau, Crime and Security and the Defence Forces Military Intelligence are also involved.

Gardaí said those suspected of being involved in such activity are believed to be involved in offering logistical and financial support for those planning or carrying out attacks abroad.

A number of people are currently before the courts in connection with such alleged activity.

A number of other people under also under surveillance in Ireland.

Gardaí also work closely with immigrant communities and have 270 diversity officers all over the country to liaise with them.

Around 30 people have travelled from Ireland to fight in the Middle East in the past seven years, five of whom died.