Saudi Arabian authorities have arrested three suspected al Qaeda members in the Red Sea port city of Jeddah, security sources said this evening.
"One of the three is cooperating with us, he is talking to security," a Saudi security source said.
It is not clear if the arrests were linked to last week's triple suicide bombings of residential compounds in the capital Riyadh, which killed at least 34 people.
The arrests, which were made yesterday, were announced hours after the US warned of possible further attacks on the Gulf state.
Following a meeting a White House meeting of top national security officials reviewing recent intelligence reports, the US raised its terror alert status to the second-highest level "high" or "orange".
The FBI said earlier in the day that recent suicide bombings in Saudi Arabia and Morocco could lead to an attack on the United States, though it said it had no specific threat information.
"Recent intelligence suggests that attacks may be a prelude to an attack on the United States," the FBI said in a message sent to law enforcement agencies across the country. "However, the FBI possesses no information indicating a specific threat in the United States."