CNN  — 

The second phase of a million-dollar online whisky auction has been postponed after it became the target of a cyber attack, auctioneers have said.

Dubbed “the Perfect Collection,” the spirits were amassed by the late Richard Gooding, a private American collector from Colorado.

Gooding spent decades in pursuit of the perfect collection, and traveled regularly to Scotland to search for special bottles at auctions and distilleries, according to the auction house, the specialist drinks seller Whisky Auctioneers.

His whole collection consisted of more than 3,900 bottles – primarily single malt Scotch – with some individually valued at more than £1.2 million ($1.4 million), auctioneers said.

The collection had whiskies from now closed distilleries.

The eclectic mix of whiskies includes rare and valuable bottles from The Macallan, Bowmore and Springbank, as well as drinks from now-closed distilleries, Stromness Distillery and Dallas Dhu.

The first part of the collection, made up of more than 1,900 bottles, sold for about £3.2 million ($3.9 million) earlier this year.

The second phase, featuring more than 1,900 bottles – including a bottle of The Macallan 1926 Fine & Rare 60 Year Old, which the Perth-based auctioneer said was expected to fetch more than £1 million at auction ($1.2 million) – went live on April 10.

Bidding was due to close at 7 pm local time on April 20, the auctioneers confirmed to CNN, but was postponed for two days, initially attributed to “abnormal excessive loads on the website, which caused some technical issues.”

Now, a statement on the website of the auctioneer says the sale had in fact been targeted by criminals.

“At approx. 22.30 (BST) on 21 April, WhiskyAuctioneer.com experienced a targeted, technologically sophisticated, sustained and malicious attack on our website and databases,” the auctioneer said in a statement on its website, adding that part two of the Perfect Collection auction had been postponed “indefinitely.”

Auctioneers said the second phase of the auction was postponed "indefinately."

“We extend our apologies to those who are disappointed in the postponement of the auction and those who may be impacted by the attack.

“The team here is working extremely hard to investigate this and minimize the impacts on our valued customers as a result of this situation,” they added.

Police in Scotland told CNN via email that they had received report of a cyber incident from a business in Perth, Scotland, on 21 April, and said that inquiries were “at an early stage.”