The Hollywood star Tony Burton, best known as for his appearances alongside Sylvester Stallone in the first six Rocky films, has died at age 78.

Burton played Tony "Duke" Evers in the film series, appearing as the manager who helped both Apollo Creed and later Rocky to hone their craft.

Burton was one of only a handful of actors to appear across all all of the first films.

He had also enjoyed a boxing career before turning to film.

Burton's younger sister confirmed his death to a local news website in the US, adding that he had been ill for a year but had never received a firm diagnosis.

She added that the actor's health had prevented him from seeing the new Rocky spin-off film Creed, released in 2015, which follows the son of Rocky's rival Apollo Creed.

Carl Weathers, who played Creed in the film series, was among those to pay tribute.