Gamma rays and neutrinos being charge-neutral are useful messengers in the search for dark matter. In this talk, we will explore the prospect of recently discovered sub-PeV diffuse gamma rays by Tibet AS gamma in search of decaying dark matter. While for indirect search through neutrinos we will focus on neutrinos produced from captured dark matter annihilation in a galactic distribution of neutron stars. We will see that both of these scenarios may probe unexplored regions of the parameter space for heavy dark matter.