Still shaken by the attacks that killed 34 people and left many injured, people here opted for a low-key weekend despite the presence of beefed-up security in the city.

Patrols have been intensified, with many subjected to meticulous scrutiny. There was a long queue of cars at all strategic locations in the city, including Olaya, downtown Batha and other areas.

As tales of courage and miraculous escape made the rounds in the city, sadness was still widespread. Few felt like enjoying the weekend, with many malls wearing a near-deserted look.

While Foreign Minister Saud Al-Faisal said that the Kingdom would make Al-Qaeda pay for the bombings and hunt down the masterminds, a US diplomat said the FBI would aid, not run, the Saudi investigation into the attacks.

“Saudi Arabia is a sovereign country and this is their investigation,” an embassy official said. “Whatever investigation is conducted by the FBI, the Saudis will be involved in it.”

A State Department official said Saudi and US investigators would look at how security issues were handled in the days before the explosion.

In Washington, Senate intelligence leaders said the attacks would have been difficult to stop even if officials had taken extra security measures.

US Ambassador Robert Jordan alleged Wednesday that before the attacks, Saudi officials had not responded to repeated requests for more protection at Western residential compounds and government installations.

He was speaking on the CBS television network’s “The Early Show.”

Saudi Ambassador to the United States Prince Bandar ibn Sultan acknowledged the request for more security in several US television interviews. But he said Jordan had sought security for only one compound — and that Saudi security successfully protected foreigners there.

“He asked for increased security at a certain compound,” Bandar told CBS News. “We passed it to the right authority, and that compound that he was concerned about was the only place where the evil people who did this attack did not cause injuries except killing the Saudi guards.”

Leaders of congressional intelligence committees said they were unaware of the details of the request or the Kingdom’s response. But the top Democrat on the Senate Intelligence Committee, Sen. Jay Rockefeller, said additional security might not have stopped the attacks.

In the past, he said, Al-Qaeda “would have a guy with a gun in a truck trying to break through a barrier and do it all himself. Here they did it differently. They had people with guns go in, shoot the security, then detonate the bombs.”

“It’s a big adjustment,” he said. “It’s them figuring out how to do things more efficiently.”

A US counterterrorism official said it was not surprising that gunmen would shoot guards before rolling in a car bomb. But the official said Al-Qaeda had never hit a civilian residential area before.

Senate Intelligence Committee Chairman Pat Roberts said such areas were difficult to protect.

“If you look at the car bombs, they were extremely powerful and you would have to have very, very tough security at levels that probably you would not foresee,” he said.

The authorities in the Kingdom have linked the attacks to an Al-Qaeda cell. They said 15 Saudis took part in the strikes, nine of them suicide bombers.

On May 7, Saudi security forces raided a house and confiscated explosives and guns. Several suspects escaped.

US counterterrorism officials said it was possible the raid headed off an even larger attack, forcing Al-Qaeda operatives to go ahead with a less potent strike than they had planned.

Also yesterday, Defense Secretary Donald Rumsfeld said there were no plans to further reduce US military ties with the Kingdom, slashed in April after the Iraq war.

“The answer is no,” Rumsfeld told reporters at the Pentagon when asked if he was concerned about the safety of a small number of US military trainers who will remain in the Kingdom.

“US forces are in danger from terrorists, just as people in the United States are in danger from terrorists from time to time,” he said. “And life goes on.”

The bombings have had their impact on events scheduled in Riyadh. A lecture on “The World in 2003: Prospects for Political and Economic Progress” by Dudley Fishburn, editor of The Economist, has been canceled.

It was due to be held on Saturday at the residence of British Ambassador Derek Plumbly.

The British Council also imposed restrictions on visitors by requiring them to fill out forms specifying the purpose of their visit.