An Islamic State-affiliated group in Saudi Arabia has urged more attacks against Shiites, after IS claimed two bomb attacks on mosques in the kingdom.
An IS suicide bomber on Friday blew himself up at the entrance of a mosque in Eastern Province, killing three people, exactly seven days after the jihadist group attacked another mosque in the oil-rich region.
The so-called Najd Province, which claimed both bombings, defended attacks on Shiites and said they should be "killed everywhere", in an audio message posted online late Friday.
The Islamic State "has ordered its soldiers everywhere to kill the enemies of religion, especially the Rawafedh (Shiites)," a spokesman for the group is heard as saying in the audio message. Shiites are "apostates" and "it is our duty to kill and displace them... wherever they may be," added the unidentified speaker.
Four people were also wounded in Friday's attack in the city of Dammam, which coincided with weekly prayers. The attack sparked wide condemnation.
The United States denounced the "brutality of the terrorists" and said it was committed to working with Saudi Arabia to fight extremism. "We deplore the brutality of the terrorists who perpetuated this violence at places of worship," said US State Department spokesman Jeff Rathke.
"The United States stands with the people of Saudi Arabia against this violence and remains committed to working with the Saudi government and our international partners to fight violent extremism in the region," he added.