CNN Exclusive: Castro brother says victims unrecognizable in photos

Ariel Castro's brothers no longer refer to him as kin. Instead, they call him "a monster" who should rot in jail after being accused of kidnapping and holding three young women hostage in his home for a decade.

"I had nothing to do with this, and I don't know how my brother got away with it for so many years," Pedro Castro, 54, said when he and brother Onil Castro, 50, sat down for an exclusive interview with CNN's Martin Savidge this weekend.

When the story first broke, the world saw all three brothers as suspects after Cleveland police arrested them last Monday and released their mugshots. It was not until Thursday that Pedro and Onil Castro were freed and investigators said the brothers had no involvement in the kidnappings.

Ariel Castro, a 52-year-old former school bus driver, remains in a Cleveland jail on $8 million bond. He's charged with four counts of kidnapping and three counts of rape.

He's accused of abducting Michelle Knight, now 32, in August 2002 when she was 21; Amanda Berry, now 27, a day before her 17th birthday in April 2003; and Gina DeJesus, now 23, in April 2004, when she was 14. DNA tests revealed a daughter born to Berry six years ago was fathered by Castro.

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"The horrific brutality and torture that the victims endured for a decade is beyond comprehension," prosecutor Timothy McGinty said.

Pedro and Onil, who have received death threats since their arrest, spoke to CNN because they "want the world to know" they had no idea their brother was keeping the women captive in his Cleveland home all those years.

How this horrific story unfolded from the start

'Who did I kidnap?'

The first sign of trouble for Onil came last Monday night as he was riding with his brother after dinner at their mother's home. Ariel suddenly turned into a McDonald's parking lot. A police cruiser pulled his car over.

"I said, 'What did you do, run a stop sign or a red light or something?'" he said. "He says, 'No, no. I don't know.'"

When Onil asked the police officer about why they were pulled over, he said, "All I can tell you is that you're in for some serious allegations."

"Maybe he wanted to get caught," Onil later speculated. "Maybe time was up. Maybe he was inside too much; he wanted to get caught. But if he did it that way, he shouldn't of went to mama's house and picked me up and put me in a car, if he knows that was going to happen."

Pedro was asleep at home when police woke him up.

"I was thinking because I had an open container warrant," he said.  "So, I didn't, I didn't know what -- I thought they was taking me in because of that."

The brothers were held in separate cells at the jail. It would be more than 36 hours before Pedro and Onil learned the real reason they had been taken into custody.

After helping a correctional officer interpret for another Spanish-speaking inmate, Pedro asked for more details about his own case. The officer wrote the word kidnapping on a piece of paper.

"I didn't have my reading glasses, I looked and I said, 'Oh, open containers.'  She said 'No, read it again.' And I said 'Oh!  Kidnapping!  What's this?  Kidnapping?'" he said. "I'm thinking kidnapping. Who did I kidnap?"

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Onil, in a separate cell and still unaware of the gruesome details, was able to see his brother Ariel briefly when Ariel walked by on the way to the toilet, he said.

"When he walked past me, he goes, 'Onil, you're never going to see me again. I love you bro.' And that was it," he said. "And he put his fist up for a bump."

Ariel spoke again as Onil was on his way to be questioned by a detective, he said.

"He goes 'Onil, I'm sorry. You didn't know nothing about this, Onil. I'm sorry, Onil.'  And that was it.  And then that's when I broke down on my way over there. I said, 'What did my brother do? What did he do?'"

Minutes later in an interrogation room, Onil got his answer from a detective, and it floored him.

"When he showed me the pictures of the girls, he asked me: 'Do you know these girls?'" Onil said.

"He says 'Have you ever seen this girl?' and I said 'No, I've never seen that girl.'  And then he showed me the other one. 'Have you ever seen this girl?' and I said 'No, I've never seen that girl.'  And he says 'That's Gina DeJesus and Amanda Berry,' and my heart fell. I just dropped, not physically, but I just, I just hit the ground."

He was familiar with DeJesus and Berry since their photos were posted throughout his community after their disappearances. "I told him 'They don't look like the girls who have been pinned up and posted up" and he said 'Yeah, that's how malnourished they are.'"

"Oh, it was just heart-dropping," Onil said.  "Just terrible when they said that, when he said that, 'It's Amanda Berry and Gina DeJesus, and they were in your brother's house.'  I just couldn't believe it because, you know, there was no signs of anything like that.  I've seen no signs."

Pedro's interrogation followed the same course.

"The detective said, 'Well, these three girls are in your brother's house.'  And I just, what, say that again. 'These three girls are in your brother's house.'  'What do you mean in my brother's house?' 'He kept them captive.'  'You mean, they're alive and in my brother's house?' 'Yes.'"

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