http://news.bbc.co.uk/2/hi/middle_east/8585247.stm
Saudi Arabia detains dozens of 'al-Qaeda militants'
Oil plant Haradh, about 280 kms (170 miles) southwest of the eastern Saudi oil city of Dhahran. File photo - 22 March 2006
Officials did not say which oil installations were being targeted
More than 100 suspected militants linked to al-Qaeda have been arrested in Saudi Arabia, officials have said
The interior ministry said 58 Saudis and 55 foreigners in three independent groups were planning to target oil facilities and security forces.
The groups had links to an al-Qaeda affiliate based in neighbouring Yemen, an interior ministry spokesman said.
Analysts say the group, Al-Qaeda in the Arabian Peninsula, has exploited instability in Yemen to set up bases.
A large group of 101 suspects, described as a network, was composed of 47 Saudis and others from Yemen, Somalia, Eritrea and Bangladesh, interior ministry spokesman Mansour al-Turki said.
The network "specialised in targeting security personnel," he said.
Map of Saudi Arabia
Al-Qaeda in Arabian Peninsula
Two other groups totalling 12 suspects, described as terrorist cells, were also arrested, he said.
Weapons, cameras, documents and computers were seized with the suspects.
"The network and the two cells were targeting the oil facilities in the Eastern Province and they had plans that were about to be implemented," Mansour al-Turki said.
"Each cell did not know about the other or their plans," he added.
'Yemen link'
There was no news on when the arrests were made or on which oil installations were being targeted and whether they were foreign- or Saudi-owned and operated.
Spokesman Mansour al-Turki said the investigation so far revealed "correspondence between this organisation and al-Qaeda's organisation in Yemen".
ANALYSIS
BBC correspondent Christian Fraser
Christian Fraser, BBC News, Cairo
The recent merging of al-Qaeda in Saudi Arabia with al-Qaeda in Yemen - as well as the group's relocation to Yemen's northern border - is now of major concern to Riyadh.
For some months the Saudis have been battling Shia Houthi separatists on the northern Yemeni border.
It is believed al-Qaeda has benefited from that instability to set up its training camps in the remote mountainous regions.
Yemen is the ancestral home of Osama Bin Laden's family. It is practically impossible to police the 1,450km (900 miles) Yemeni-Saudi border because of the rough terrain and tribal opposition.
There are plenty of Saudis and Yemenis opposed to the close Saudi association with the rich oil-producing companies of the West.
The capacity of these Yemeni-based al-Qaeda militants to launch attacks beyond the border was underlined in August 2009 by the assassination attempt on Saudi Arabia's top counter-terrorism official.
Al-Qaeda in the Arabian Peninsula (AQAP) was formed in January 2009 by a merger between two regional offshoots of the Islamist militant network in neighbouring Yemen and Saudi Arabia.
Led by a former aide to Osama Bin Laden, the group has vowed to attack oil facilities, foreigners and security forces as it seeks to topple the Saudi monarchy and Yemeni government, and establish an Islamic caliphate.
Saudi Arabian security forces have managed to prevent large-scale attacks in Saudi Arabia in recent years, with hundreds of suspects arrested.
But AQAP's first operation outside Yemen targeted Saudi Arabia's security chief, Prince Mohammed bin Nayef, last August.
A suicide bomber managed to detonate his explosives close to the prince, giving him minor injuries.
In May 2003, suicide bombers suspected of having links with al-Qaeda killed 35 people in the capital, Riyadh. The victims included a number of foreigners. Later that year, 17 people were killed in another suicide attack on Riyadh.
In May 2004, at least 30 people were killed in Khobar when gunmen stormed a residential compound for oil workers.