finding the value of $\sum_k (-1)^k \binom nk^2$

Question

I am trying to find the value of: $$\sum_k (-1)^k {n \choose k}^2$$ The hint is that $(1-x^2)^n = (1-x)^n(1+x)^n$

I tried solving it using convolution but it didn't quite work.