A Dutch woman and her 17-year-old son -- who between them swallowed cocaine pellets worth over €52,000 -- have been arrested at Dublin Airport.

They were among seven people caught trying to smuggle drugs at the airport in the past week.

The 47-year-old woman and her son arrived on a flight from Amsterdam. They were stopped at customs and found to have swallowed almost a kilogramme of cocaine pellets between them, worth an estimated €52,500.

A 44-year-old Latvian man, with an address in Dublin, also aroused the suspicions of customs officers when he arrived on a flight from Paris having earlier started his journey in French Guyana. He was found to have swallowed one kilogramme of cocaine worth €70,000.

A 17-year-old Irish youth was stopped when he arrived from Alicante and was discovered to have 1,248 sleeping tablets in his possession. A file is being prepared for the Republic's Director of Public Prosecutions by the Irish Medicines Board.

Officers discovered 9kgs of cannabis, worth over €100,000, in the suitcase of a 25-year-old Polish man when he arrived on a flight from Charleroi Airport in Belgium.

In the biggest haul of the week, a 25-year-old Irish man was caught with 39,000 Valium tablets worth €200,000. He had arrived on a flight from Abu Dhabi having earlier left Bangkok in Thailand. The drugs were found concealed in his luggage.

A sniffer dog was used to catch another Irish man who was found in possession of a quantity of heroin and cannabis after he arrived from Amsterdam.

Meanwhile customs officers seized 289,000 cigarettes and 50kgs of tobacco in an operation targeting smuggling gangs from Latvia, Romania and Northern Ireland.

So far this year, officers have seized almost 25million cigarettes and 1,000kgs of tobacco at Dublin Airport. This represents a potential loss to the Revenue of €7.5m.