are -- >> approximately how many have died? >> i understand your question, sir. i will get back to you. >> reporter: the intense scrutiny surrounding the deaths of two children in cbp custody this month is forcing changes, beefing up their medical screenings and focusing on migrant children under 10 years old. an agency already stretched thin from what it calls a dramatic increase of apprehensions of units, is now facing new demands for accountability with the deaths of two children. others questioning the effectiveness of president trump's much-touted wall from stopping migrants from crossing the border. >> i want to point out that phillipe and his father were apprehended in the el paso sector where a wall already exists. and this tragedy should be a wake-up call to folks who believe that mythology about walls. they just do not work. >> reporter: this as another group of migrants were dropped off at a bus stop in el paso, texas, after being held in custody.