Brasilia, March 10 (RHC) -- Brazil President Dilma Rousseff has reiterated her concern about racism in soccer after a spate of incidents involving Brazilian players and officials, Xinhua news agency reported.

In comments posted on Twitter, Rousseff expressed her support for former Brazil international mid-fielder Arouca, who was racially abused by a fan while representing Santos against Mogi Mirim in the Sao Paulo state championship last Thursday.

"It's inadmissible that Brazil, the country with the largest Black population out of Africa, has racism issues," Rousseff said.

Last week's incident came a day after racist chants were directed at referee Marcio Chagas da Silva during the Rio de Janeiro state championship match between Esportivo and Veranopolis.

And in February, Cruzeiro midfielder Tinga, also a former Brazil international, was subjected to monkey chants by Real Garcilaso fans during a Copa Libertadores match in Peru.

Rousseff also pledged to make the anti-racism message a theme of this year's World Cup. The Brazilian president said: "We are going to take on racism. We have agreed with the United Nations and FIFA that this will be a World Cup against racism."