Two people were shot dead in Saudi Arabia in a gunfight between police and gunmen at the funeral of a man killed earlier in the week, officials said.
The shooting took place in the oil-producing Eastern Province, state media quoted the interior ministry as saying.
Eastern Province is home to Saudi Arabia's Shia minority and has seen a number of protests recently.
The interior ministry said the gunmen were working for a foreign country, an apparent reference to Iran.
"These casualties have occurred due to the exchange of gunfire with unknown criminal elements who have infiltrated among citizens and are firing from residential areas," the interior ministry said in a statement quoted by the Saudi Press Agency.
Saudi Arabia has blamed Iran for fomenting unrest in its tiny eastern neighbour Bahrain, a Shia majority country ruled by a Sunni monarchy.
Bahrain is reached by a causeway from Eastern Province. Saudi troops crossed into Bahrain earlier this year to help the government put down protests.
"The goal of those who provoke unrest is to achieve dubious aims dictated to them by their foreign masters," the interior ministry said.
Iran, Saudi Arabia's rival for influence in the Gulf region, has denied involvement in Bahrain's unrest.
The statement said a number of security checkpoints in Eastern Province have come under attack this week.
The funeral where the latest shooting took place was for somebody killed in one of those earlier attacks, the interior ministry said.
Witnesses quoted by AFP news agency said the two killed in Wednesday's shooting were Shia men at a demonstration during a funeral.
A total of four people have been killed this week in Eastern Province, the interior ministry said.
Saudi Arabia has not experienced the mass protests seen in other countries in the Middle East. When the Arab Spring broke out earlier this year, Saudi authorities unveiled a huge package of spending on housing and other benefits as well as an expansion of its security services.