At least two people died and scores were injured as Saudi police clashed with foreigners in a poor district of Riyadh, nearly a week into a visa crackdown in which thousands have been detained.
Security forces in riot gear fired into the air and used truncheons to disperse large crowds on Saturday in Manfuhah, as scores of men ran through the streets, some throwing stones and other objects at cars and police, according to Reuters witnesses.
The Saudi police said late on Saturday that two people were killed, one of which was a Saudi while the other was unidentified. The police added that 68 people were injured, and 561 people arrested.
Most of the foreign workers involved in the clashes appeared to be Africans.
In some streets in Manfuhah, men in Saudi dress had also gathered in small groups, some of them carrying knives and iron bars, saying they were protecting their property.
Authorities this year said they would no longer ignore foreign workers breaking visa rules by working for companies that had not sponsored their entry into the country
The intention is to end a black market for cheap imported workers, cut the foreign labour force, reduce the flow of remittances to other countries and make more private sector jobs available for Saudi citizens.
Foreigners were given a seven-month amnesty to rectify their visa status without penalty or leave the country, prompting hundreds of thousands to leave. Thousands more have been arrested since the amnesty expired on Monday.
On Wednesday, an Ethiopian was killed in a raid after he tried to grab a policeman's weapon, the Arab News English-language daily reported on Friday.
Many expatriate workers say they were unable to take advantage of the amnesty because of bureaucratic difficulties or disputes with their original sponsors.