A law lecture at the University of Aruba attended by the Dutch king, queen and princess Amalia was disrupted for a few moments on Tuesday as a demonstrator held up a flag and began singing the civil rights campaign song Oh Freedom.

Gisele Sint Jago, a master’s law student who is an activist for local party Pueblo Prome, was led out of the room while the Dutch royals looked on. The lecture was resumed shortly afterwards.

The king, queen and Amalia arrived on the Caribbean island of Bonaire on Friday at the start of a 10 day visit which will take in all six of the former Dutch colonies. The islands’ slavery past is one of the visit’s key themes.

Sint Jago told broadcaster NOS later she had aimed to hand a statement to the king, calling on him to offer his excuses for the Dutch role in the slave trade. Pueblo Prome is also campaigning for restitution for the descendants of enslaved people and for slavery to be considered a crime against humanity, NOS said.

Dutch prime minister Mark Rutte formally apologized for the Dutch state’s role in slavery on December 19 after weeks of criticism. Campaigners wanted the apology to be made on Keti Koti on July 1, when 150 years since the actual end of slavery on the islands and in Suriname will be celebrated.

The king will be at the Keti Koti commemorations this year but nothing has been said about an apology.