At least two people were killed when a car exploded in Saudi Arabia's eastern city of Qatif on Thursday, Saudi-owned Al-Arabiya television reported.
It said initial reports indicated the victims were "fugitives", a term that suggested people being sought by the kingdom's security services.The channel had earlier said the blast was caused by a car bomb. Its website posted images of thick black smoke rising from a street.
A resident contacted by telephone by Reuters said he had heard a blast and saw smoke rising above an area that police had blocked off. Saudi authorities were not immediately available for comment.
Photos sent over social media showed a body apparently completely burned being pulled from the wreckage of a car. The authenticity of the photos could not immediately be verified.
A witness told AFP that emergency vehicles converged on the scene.
"The explosion was very huge," the witness said, asking not to be identified.
Armoured and other police vehicles sealed off the area after the explosion, the witness said.
The IS in 2014 began a campaign of bombings and shootings that has killed more than 40 Shias in Saudi Arabia's Eastern Province, which includes Qatif.
In August, police said they shot dead a would-be suicide bomber targeting a mosque in Qatif district.
Two months later, a gunman killed five people at a Shia meeting hall in Saihat district of Qatif.
