U.S. officials planning the May 2 raid on Osama bin Laden’s compound worried about possible escape routes he might use if he somehow got advanced warning of the attack, according to Leon Panetta, who helped oversee the effort as CIA director.

But that advanced warning apparently never came.

“I can’t tell you that it was a Pakistani individual or ISI [the Pakistani intelligence service] or anybody else that would provide that warning, but I am convinced that somebody was targeted to provide that warning in the event that something like that would happen,” Panetta, now secretary of defense, said in an interview with Charlie Rose that aired on PBS Tuesday night.

During planning sessions for the early morning raid on bin Laden’s compound in Abbottabad, Pakistan, U.S. officials discussed how bin Laden could escape once an attack took place, Panetta said.

“Our suspicions were always, ‘Well, they’ve got to have a tunnel for an escape. They’ve got to have, you know, a hole in the wall that they can hide in. They’ve got to have a way to get out the back door if there’s any kind of raid. Surely they’ve planned for all of that.’”

But when the two U.S. helicopters arrived and Navy Seals killed two bin Laden aides and a son in a firefight on the ground floor, they found and shot the al Qaeda leader in his third room. The fact he was still there gave Panetta the sense that bin Laden believed he’d know in advance if there was any attack coming.

“When he was trapped on the third floor of that compound, what it told me is that he was hoping to get some kind of warning if something like that were to happen,” Panetta told Rose.

No Pakistanis were told ahead of time. Secrecy held.