A high powered Garda investigation is continuing after a lorry driver from St Johnston was arrested in Dover with a drugs haul.

The man in his 40s was arrested after heroin with a street value of up to ¤1million was found in his lorry by police at the port. He had been travelling into England from Calais in France.

While Gardai remained tight lipped about the matter a senior source confirmed in a follow up operation that the man's house in the St Johnston was searched by members of the Garda Drugs Unit over the past week.

"We were notified of this seizure by police in Dover and asked to search this house as part of the follow up operation," the garda source said.

"We were searching for any information that would suggest this man had full knowledge of what he was doing or that he may have been duped into taking the heroin into England," he added.

The lorry was impounded by police and the man was taken into custody for questioning.

"This was a very significant find and as part of our investigation our enquiries are ongoing and we'll be assisting the police in whatever we that we can," he said.

"Officers from the Drugs Unit are keeping in close contact with their colleagues in Dover as part of the investigation.

"We're not sure where the drugs were destined for," the senior garda source said.

Late last year Officers from the Revenue's Customs Service in Letterkenny seized 60 kgs of Cannabis resin with an estimated street value of ¤420,000.

The two bales of cannabis had been found by a Donegal based fishing trawler while fishing off the west coast.

The bales had been very well wrapped and from their condition it is believed that they have been in the sea only for a short period.

The skipper of the trawler had immediately advised Customs of the find and Customs officers and Gardai met the trawler on its return to port.

The find was made relatively close to the area where 261 kgs of cannabis was found in September by another trawler fishing in the area.