A firefight in a mainly Shia area of eastern Saudi Arabia killed four people, including two policemen, on Thursday, the interior ministry said.

The police clashed with two wanted activists in the flashpoint Awamiya district of the oil-rich Eastern Province, both of whom were also killed, a ministry statement carried by the official SPA news agency said.

The clash came a day after a Saudi court jailed seven protesters for up to 20 years for joining a demonstration and chanting anti-government slogans in the Eastern Province.