At least 30 people died and more than 200 were injured as explosions rocked the Saudi capital just hours before Powell's visit, reports John Bradley from Riyadh Four huge explosions rocked the Saudi Arabian capital late Tuesday evening, just hours before the arrival of Colin Powell, the US secretary of state. There were widely varying casualty estimates. Vice-President Dick Cheney said at first that 91 people had been killed in the attacks. State Department officials said later they expected the toll to be at least 40, including the already confirmed seven Americans. Nine suicide bombers died. The company headquarters of a jointly owned US-Saudi firm, responsible for training members of de facto leader Crown Prince Abdullah's elite National Guard, was hit minutes after simultaneous suicide attacks on three residential compounds, which were mostly home to Western expatriates. US President George W Bush said those responsible would be tracked down, adding that he "wouldn't be surprised" if Al-Qa'eda was behind the Saudi attacks. Powell, who visited one of the bomb sites, also pointed the finger squarely at Al-Qa'eda. Saudi Interior Minister Prince Naif immediately said Al-Qa'eda was responsible, and made a direct link between the nine-member Al-Qa'eda cell raided by Saudi security forces on 6 May and the carnage brought about by the four bombs in the capital. All 19 members of the cell -- 17 of whom are Saudi -- escaped the initial raid though a huge cache of arms and explosives was netted. The raided hide-out used by the cell was just a few kilometres away from one of the subsequent suicide attacks, raising questions about how Al-Qa'eda operatives apparently on the run could have organised and carried out such extraordinarily well- timed and executed attacks. Anti-Western sentiment is at an all-time high in Saudi Arabia, with ordinary Saudis furious at the US-led war on Iraq and Israel's continued violent suppression of the Palestinians. However, there was near-universal condemnation of the latest attacks, with the exception of those who visited Islamic Jihad Web sites to post their words of praise for the "martyrdom" operation. The suicide bombings came after the US State Department issued a warning about an imminent Al-Qa'eda attack in Saudi Arabia on 1 May. Following the bombings the State Department issued a new travel warning and ordered all nonessential diplomatic personnel and family members from the official American community to leave. An American resident of the Al- Hamra compound in the east of Riyadh near the airport, scene of the largest of the explosions, told Al-Ahram Weekly that a number of men had fought their way through the heavy security at the compound, firing Kalashnikovs. They then parked their car inside and shortly afterwards it exploded. "There were bodies all over the place," a Saudi resident at the compound told the Weekly. "There was blood everywhere." Another Saudi national, who was driving through the outskirts of the capital when the attacks occurred, said that he saw a huge fireball over the city at the time of the explosions. "It was absolutely spectacular," he said. Hundreds of anti-riot police and members of the National Guard immediately converged on the attack sites, leading compound residents to safety and sealing off the areas of the explosions. The following day Saudi TV broadcast scenes of utter devastation as Prince Abdullah condemned the attacks as "monstrous". A day before the bombings a Saudi Islamist group believed to be close to Saudi dissident Osama Bin Laden's Al- Qa'eda network called for revenge attacks on US interests following the huge seizure of arms from militants in Riyadh the week before. The Mujahideen in the Arabian Peninsula urged its followers to "strike and destroy American interests on land, at sea and in the air" in retaliation for the seizure of the weapons and explosives following a shoot-out in the Saudi capital. "It is absolutely necessary that we all be united in the war against the aggressors and that we pursue them all over the world," said the group. The statement said the munitions were "intended to kill the Crusaders, who are attacking our brothers in Palestine, Afghanistan and Iraq". It continued: "We are preparing to take our revenge... It is our duty to prepare the means to terrorise the enemy."