In a shocking development in the Natalee Holloway case, police believe Joran van der Sloot and his two pals were all with the blonde beauty when she died, The ENQUIRER has learned exclusively.

And they are close to identifying the boat they believe took the Alabama teen to her final resting place.

While others speculated on the new evidence that led to the dramatic Thanksgiving busts of 20-year-old Joran and brothers Deepak and Satish Kalpoe, The ENQUIRER penetrated the top secret investigation.

We learned exclusively that the three suspects were nailed by a young undercover cop who spent months becoming Joran’s buddy in Holland. Incriminating evidence was also gathered by phone taps.

“Police now believe they know where Natalee is – at the bottom of the ocean,” an Aruban insider told The ENQUIRER.

Natalie, 18, vanished in May 2005 during a graduation trip to Aruba. She was last seen being driven from a popular bar with Joran, Deepak, 24, and Satish, 21.

Joran told police the brothers dropped them off on the beach – and that after he and Natalee made out, he walked home, leaving Natalee alive and well about a half mile from her hotel.

But the phone taps – and details Joran drunkenly let slip to the undercover cop at school – tell a different story, The ENQUIRER has learned.

Pick up the new issue of ENQUIRER for all the details!