Bexar County sheriff's investigators spent the night searching a home near Elmendorf for possible explosives.
Meanwhile, they are still looking for the man who lives there, Raul Casas Campos, 34.
Campos is accused of carrying out a brutal sexual assault of his ex-girlfriend Monday after luring her to his home in the 13000 block of Laguna Road, then forcing her inside at gunpoint.
In a news conference Monday night, Sheriff Javier Salazar told reporters that deputies had arrested a different man who they caught leaving Campos' residence wearing a bullet proof vest and carrying a grenade.
He said a K9 also indicated that there were explosives inside the home.
So far, there is no word on what, if anything, was found in the home during the search.
Campos, however, is still on the loose.
Salazar said anyone who encounters him should contact authorities because he is armed and dangerous.