It looks like a Diplopoda, but I've never seen anything like that. A friend took those pictures in the Brazilian Cerrado (Goiás state, Brazil) these days (October, start of rainfall in Spring). It was inside a country house, she already found it dead.
She said it has about 3 cm (~1.2") long. We can see it's not so small as a Symphyla or Pauropoda. Looks like it has 12 pairs of legs.