I've always been told DuckDuckGo is a clearnet search engine. However, in some of my recent searches on researching onion services I've managed to get search results with an onion service URL. I've gotten the Hidden Wiki onion service and even the Silk Road onion service. So does DuckDuckGo crawl the dark web or just have a collection of links to certain onion services and these URLs just come in the search results if the search seems to be on one of these onion services? Also, should DuckDuckGo still be considered a clearnet search engine even if it has dark web results for certain services or is it something different?
Images for reference:
Note: In no way do I encourage searching up on DuckDuckGo and going to these hidden services especially if they doing something illegal. I'm just using these search results for a question for research purposes.