A three-day shootout near Saudi Arabia's capital was brought to a close Tuesday with a large number of militants killed or captured, Sherine Bahaa reports It was the longest gun battle between militants and Saudi security officials since the kingdom's war on terror began in May 2003 following a series of kidnappings and bombings. The location was all-too-close to the Saudi capital, only 32 kilometres north of Riyadh. Security officers received a tip-off about a group of militants being sheltered at a villa in the desert town of Rass. The battle began Sunday morning with the arrival of several hundred state security officers at the building in the Jawazat district, known as a stronghold for extremists. At first, officers said the fighting would be finished within hours with police waiting for the men -- according to first reports, 10 in total -- to surrender. "They were asked to surrender, but those people are known not to listen," said the local governor, Prince Faisal Bin Bandar Bin Abdul-Aziz. As the tense standoff entered its second and third days, it was clear that the Jawazat district villa was not just a temporary residence for militants but rather an arsenal for heavy weaponry and grenades. And the number of militants also rose. In total, 18 militants were reportedly killed while six others were arrested in the 72-hour battle. More than 52 special security officers were hospitalised, although medical reports talked only of minor injuries. Among the 18 killed were two top figures in "the deviant group", as Saudis call groups affiliated to Al-Qaeda. The two, ranked four and seven respectively on Saudi Arabia's list of most wanted Al-Qaeda-linked terror suspects issued in December 2004, are Karim Al-Tohami Al-Mojati and Saud Homoud Obaid Al-Otaibi. Al-Mojati was a battle-hardened fighter who fought in Afghanistan and was described as a supporter of Al-Qaeda leader Osama Bin Laden. True or not, Al-Mojati was claimed to be one of the masterminds behind the Casablanca bombings in 2003 in which 33 bystanders were murdered. Al-Otaibi is said to have been co-running Al-Qaeda's branch in Saudi Arabia. Last year, Al-Otaibi purportedly posted an internet statement rejecting an amnesty offered by Saudi ruler King Fahd promising militants safety if they surrendered. Saudi security officials declined to confirm the killing of the two figures until DNA tests could be completed. Saudi journalist Zuhair Al-Harithi told Al-Jazeera from Jeddah that if reports proved right, it would be "one of the biggest and most significant operations Saudi forces have ever carried out". In a statement read on Saudi television, Saudi Crown Prince Abdullah congratulated the security forces, who had "demonstrated their courage in facing up to terror acts. We thank each one of them for their heroic deeds." For several months after the attacks on the US on 11 September 2001, Saudi officials denied that the kingdom had a problem with terror, even though 15 of the 19 hijackers would turn out to be Saudi. Any such illusion was very publicly shattered in May 2003 when militants launched multiple gun and bomb attacks on housing compounds in Riyadh. At least 29 people died, including nine attackers. Since then, although vast quantities of arms have been seized, hundreds of suspects rounded up and 21 of the 26 men on the kingdom's most-wanted list arrested or killed, attacks have continued. Among the latest was an attempt to storm the US Consulate in Jeddah last December; an attempt that left five staff and three attackers dead. Later in the same month car bombs targeted the Interior Ministry and a special forces training centre in Riyadh.