Gardaí are investigating the kidnapping of the family of a cash-in-transit employee and a subsequent robbery in Dublin today.

A gang of around four masked and armed men took the employee, the man's mother and nine-year-old niece hostage from their home on Bath Avenue, Irishtown, at around 6.30am this morning.

The gang gave the man a mobile phone and told him to go to the Bank of Ireland in O'Connell Street where the company he worked for, Brinks Allied, was delivering cash.

The man arrived there in a white Renault van at around 11.30am and took a number of cash boxes away.

He drove the van and the money to Drumcondra as instructed by the gang and left it for them to collect in a hotel car park.

He then took the DART to Bray, Co Wicklow, where he reported the crime to the gardaí at 2pm.

The man's relatives were held hostage before being released in the New Vale Crescent estate in Shankill, Co Dublin at around 12.30pm.

The man and his two relatives were severely traumatised by their ordeal but otherwise unhurt and detectives are interviewing them to get more information on the gang.

Gardaí are still trying to establish how much money was stolen but it is believed to be just over €100,000.