Britney Spears sister claims pop star 'locked her in room with KNIFE'

Britney Spears sister, Jamie Lynn Spears is detailing shocking revelations of the singer's 'erratic' behaviour in the past.

Speaking to Good Morning America host Juju Chang, the 30-year-old shared that Britney once locked both of them in a room with a knife.

"First off, I think that experiencing my own panic attacks and how sometimes we can feel in those moments is important, but also it's important to remember I was a kid in that moment," she replied.

Jamie Lynn added: "I was scared. That was a moment I had. I also was fearful to really say anything because I didn't want to upset anybody, but I also was so upset that she didn't feel safe."

The pop star's sister has detailed the incident in her memoir Things I Should Have Said.

Further sharing how Britney was 'erratic, paranoid and spiraling' Jamie revealed how she was screamed at in front of her children a few years after.

"She cursed at me and so I just walked out of the room, we're all family, I'm not trying to argue. When I tried to remove myself from the situation, that's when I guess she got really angry and my oldest daughter tried to mediate the situation. I hated that," Jamie Lynn claimed.

"That's not what you're supposed to do, you're 12. [My parents] told me I can't upset Britney. I'm like, you saw me and my children get upset, when will that matter?"