West Memphis Police Chief Bob Paudert said agents of the Bureau of Alcohol Tobacco and Firearms advised him of the press conference and told him to be there.
Paudert said he and ATF agents are "comfortable we will solve this."
Pierce was burned and maimed by shrapnel when an explosive device went off Wednesday morning in his yard while he was near his car. The precise location and nature of the device have not been disclosed.
"I think we will uncover some information rather quickly that will lead us in the direction we need to go," Paudert said.
The Flyer will update this story following the news conference.