On algebraic independence of certain multizeta values in characteristic p

In this paper, we study multizeta values over function fields in characteristic $p$. For each $d \geq 2$, we show that when the constant field has cardinality $> 2$, the field generated by all multizeta values of depth $d$ is of infinite transcendence degree over the field generated by all single zeta values. As a special case, this gives an affirmative answer to the function field analogue of a question of Y.\ Andr\'e.