These attacks are only part of the growing security concerns sweeping the energy industry across the turbulent Middle East and the Gulf of Guinea region, the center of West Africa's oil boom.
While there does not appear to be a coordinated plan to sabotage oil and gas production in these regions, al-Qaida has consistently targeted oil facilities, from pipelines to Saudi Arabia's massive Abqaiq oil processing complex on the Persian Gulf Feb. 24, 2004, seeking to cut off the industrial world's energy lifeline.
The recent resurgence of attacks, including the seizure by jihadist gunmen of the sprawling In Amenas gas facility in Algeria in which 37 expatriates were killed, indicates that energy installations are again in the crosshairs.
In Libya, a major North African oil and gas producer, the energy sector which is the country's economic mainstay has been severely disrupted since February 2011 when the uprising against dictator Moammar Gadhafi erupted.
Oil production of 1.6 million barrels a day was shut down. It was reopened after Gadhafi was toppled and killed in October 2011, but it's still curtailed, from production to refining to exporting, by armed militias which the new government cannot control.
In the Gulf of Guinea, the oil industry's been hit by a surge in piracy in which offshore platforms and tankers are prime targets.
Following the attack on In Amenas, a facility run by BP and Norway's Statoil with Algeria's state-owned Sonatrach, international energy companies say they're forming special security units to respond to terrorist strikes.
Britain's Foreign Office has invited British companies operating in risky regions to stage "war games" in which company executives and FO officials will thrash out responses to potential foreign crises involved their employees.
Intelligence officials have warned that attacks like In Amenas could become more common because al-Qaida and its North African allies are finding it difficult to mount operations in Europe.
In Iraq, the energy industry has become a strategic target for al-Qaida because crippling it would undermine the government's plan to triple production to finance massive national reconstruction.
The pipeline between Baiji and the Turkish border is being hit at least once a month, reducing its already minimal flows of 153,000 barrels per day in June, one-tenth of capacity.
There are twin 600-mile pipeline from Kirkuk to Turkey's Ceyhan terminal on the Mediterranean which have a maximum capacity of 1.6 million bpd.
Iraq's energy infrastructure, which provides around 90 percent of the country's revenue, has been a regular target since the U.S. invasion of 2003, particularly the northern sector centered on the Kirkuk oil fields.
These run through Sunni-dominated regions where al-Qaida's particularly active. In recent months, the insurgents have extended their raids to the south.
This is where the country's megafields, which hold two-thirds of Iraq's state reserves of 150 billion barrels of oil, are located and this is where international companies are concentrated.
Al-Qaida's southward thrust has alarmed these companies in the provinces of Basra, Maysan, Dhi Qar and Muthanna.
Security officials say that in the last three months, there have been 14 major attacks in the city of Basra alone, several caused mass casualties.
On July 3, a double car bomb attack targeted Basra's Minawi Basha Hotel, one of the few hotels used by foreign oil companies.
"Although the attack did not kill or seriously injures any oil company employees it would only take one very successful attack or regular near-misses to prompt a re-think about the expatriate presence in Iraq," Oxford Analytica observed.
An exodus of foreign oilmen would seriously curtail Iraq's production level of around 3 million bpd, and undermine its drive to boost output to 9 million bpd by 2020.
Security officials fear al-Qaida plans to step up its attacks following the escape of some 400-500 inmates in a mass breakout from Abu Ghraib prison outside Baghdad Sunday during an attack by the Sunni extremists.
The escapees included hundreds of seasoned al-Qaida fighters and several commanders who will reinforce the group's offensive in Iraq as well as in neighboring war-torn Syria.
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