Let $\overrightarrow{a}, \overrightarrow{b} \text{and} \overrightarrow{c}$ be three non - zero vectors such that no two of them are collinear and $\left(\overrightarrow{a}\times \overrightarrow{b}\right)\times \overrightarrow{c}=\frac{1}{3}\left|\overrightarrow{b}\right|\left|\overrightarrow{c}\right|\overrightarrow{a}$. If $\theta$ is the angle between vectors $\overrightarrow{b}\text{ and} \overrightarrow{c}$, then a value of $\sin \theta$ is