MADRID (AP) — Spanish arms control groups staged a protest Tuesday against the presence of a Saudi cargo ship they suspect is carrying weapons for use in Yemen.

The Bahri Abha ship arrived early Tuesday at the eastern port of Sagunto from the United States, according to activists. The Control Arms Coalition of human rights and aid groups staged a small protest at the port and called on the Spanish government to prohibit the transit and loading in Spain of any weapons likely to be used to commit war crimes.

Amnesty International, a member of the group, says the ship has carried weapons, mostly military aircraft components, on eight voyages from the United States to Saudi Arabia.

The ship left Sagunto early Tuesday afternoon, port authorities said. They said the ship had carried out fully legal cargo operations but could not say what the ship was carrying or where it was now headed.

The Bahri Abha visited several ports in the United States before traveling to Spain, Amnesty said in a statement. Amnesty said it was not known if it was carrying arms on its current voyage.

Countries are under pressure not to send arms to Saudi Arabia amid concerns they are being used against civilians in Yemen where thousands have died since the conflict began in 2014.