The FBI sought a search warrant to seize plastic bags with "crystal-like substances" inside the van of Lorenzo Salgado Araujo, who was fatally shot by an immigration agent last week.

The FBI said it suspects methamphetamine, but the lawyer representing Salgao Araujo's brother on Thursday said it was granulated salt.

"After consulting with my client and his family, our understanding is that this was granulated salt, which is paired with lemon and water as a homemade electrolyte mix used by outdoor workers in extreme Texas heat, not methamphetamine or any other illicit substance," said Ruby Powers, a Houston immigration attorney representing Victor Hugo Salgado Araujo, who was the front passenger inside the van.