Tayside Police recovered 9.1 kilos of heroin in 2005/06, compared with 5.7 kilos during the preceding 12 months. The number of seizures was also up, from 246 to 325.

During the last year there were a number of high-profile operations in the region, including the conclusion of a crackdown on a crime operation based in Dundee.

The Executive figures also revealed the total number of drug seizures in Tayside hit a new peak last year — more than twice the number of a decade ago, at 2062.

There were big increases in the amount of cannabis resin and number of cannabis plants recovered.

Across Scotland, there were rises in a variety of categories, and Justice Minister Cathy Jamieson branded the people who peddle illicit substances, “a scourge on our communities”.

“The increase in the number of hard drugs seized shows strong enforcement action is paying off,” she said.

“An important element of this work is the Executive’s Drug Dealers Don’t Care campaign, which has resulted in over 5000 calls to Crime-stoppers, 530 arrests and seizure of over £1.6 million worth of cash and drugs.

“Professional police and a committed, involved public send a powerful message to dealers that Scotland is determined to stand up to them.

“However, enforcement alone will not stop the terrible impact drugs have on our country. We need to be alive to the emerging threats of crack and cocaine and ensure we have measures that keep more of our young people free from drugs.

“The Know the Score campaign and other education programmes in our schools are helping prevent young people from being lured into taking drugs.

“Illegal drug misuse is a difficult and ever-changing problem. We have increased the number of treatment places and have nearly doubled our investment in treatment to ensure people are helped to get drug free.”