Check out this footage we obtained, which we shot around 3 PM PT Monday -- a couple hours after the raids at his homes got underway -- at the Miami-Opa Locka Executive Airport ... where eyewitnesses tell us Diddy and some other people got stopped by the feds.

We're told this shows Diddy pacing around outside a Customs office there at the airport -- and as you can see ... he's not being detained, and he certainly doesn't seem to be in custody here. Instead, Diddy is just walking around all by his lonesome.

An eyewitness tells us Diddy was waiting on other people in his party here -- who were stopped and questioned by the feds as well during this whole ordeal -- but we haven't been able to confirm who was rolling with him yet.

All we know is he and his crew got stopped at Opa Locka, where we're told he appeared to be aboard a separate private jet ... and that's when Homeland Security rolled up.

While it might seem strange that Diddy wasn't cuffed, it actually tracks with what we've heard about his situation thus far -- namely, sources with direct knowledge tell us he is not under arrest at this point. And more importantly, he obviously isn't on the run either.

As we reported ... two separate raids in L.A. and Miami went down Monday -- where Homeland Security agents barreled through his homes and escorted some people out.

There are still a lot of unanswered questions, but it would appear law enforcement officials are probing federal crimes that have been alleged against Diddy of late in several lawsuits ... including alleged sex trafficking, all of which Diddy has denied again and again.

NBC News reports that federal officials have already spoken to three women and a man pertaining to claims of sex trafficking, among other allegations, and other interviews are supposedly scheduled to go down in the near future.

We've reached out to Diddy's camp ... so far, no word back.