An Ethiopian migrant has been killed by Saudi police after he tried to flee arrest during a round-up of thousands of foreigners suspected of working illegally in the kingdom.

A statement on Wednesday by Riyadh police chief Nasser el-Qahtani said security forces killed the African migrant worker in el-Manhoufa a day earlier when he and others tried to resist arrest.

The security sweep comes after seven months of warnings by Saudi Arabia's government, which has created a task force of 1,200 Labour Ministry officials who are combing shops, construction sites, restaurants and businesses in search of foreign workers employed without proper permits.

More than 16,000 people have already been rounded up, according to authorities.

Strict labour law

Police have also erected checkpoints to enforce the kingdom's strict labour rules that make it almost impossible to remain in the country without official sponsorship by an employer.

Residents said most shops have been closed since the sweep began on Monday, with many of the country's migrants avoiding the streets where they face possible arrest.

The state-backed Saudi Gazette reported on Wednesday that residents are already feeling the brunt of the everyday work the migrants provided, from ritual washings of corpses before burial to food delivery and bagging groceries.

Authorities say that since warnings were issued earlier this year, almost seven million foreigners in Saudi Arabia corrected their paperwork to accurately reflect their occupation and workplace.

The kingdom also issued more than one million final exit visas, which ban people from ever returning.

The Saudi-owned Asharq al-Awsat newspaper reported that authorities detained around 16,500 workers in the first 48 hours of the nationwide crackdown.

The newspaper quoted Saudi officials as saying that nearly half of the migrants were arrested near the southern border with Yemen.

Another 5,000 had been detained in Mecca, where some Muslims stay on illegally after pilgrimage.

Less than 1,000 were detained in the main city of Riyadh.

A resident in the poorer neighborhood of el-Manhoufa in Riyadh told the Associated Press news agency he saw police stopping people outside a mosque after prayers and arresting those who did not have the correct papers on them.