A rocket landed at the headquarters of several global oil companies in Iraq's southern city of Basra on Wednesday, wounding three Iraqi workers and raising alarm amid rising tensions between the US and Iran in the region.

The rocket hit the Burjesia residential and operations headquarters west of Basra, Iraqi police said. The site is home to a number of international oil giants, including US firm ExxonMobil, Royal Dutch Shell PLC, and Italian Eni SpA.

Al Jazeera's Charles Stratford, reporting from Basra, said a local security official confirmed Exxon evacuated 21 foreign staff in the immediate aftermath of the incident.

"The oil ministry is saying that oil production in the area has not been affected by this attack," Stratford said, adding the security official described the rocket used as a Katyusha.

"[But] we are seeing what can only be described as an increase in the frequency of such incidents, over the last month and a half there has been a number involving rockets fired at what has been interpreted to be foreign interests here," he added.

According to security official Mahdi Raykan, the Katyusha rocket landed at dawn in the Zubair and Rumeila oil fields camp, operated by the Iraqi Drilling company, where Exxon Mobil and other foreign oil companies have tents.

Raykan said the rocket was fired from a distance of up to 5km.

Workers of the foreign companies were not on site at the time but still in their sleeping quarters, said another Iraqi official, speaking on condition of anonymity because he was not authorised to address the media.

Oil attacks continue

Wednesday's incident was the latest in a spate of attacks on oil infrastructure in the region and came after the United States evacuated hundreds of diplomatic staff from its embassy in the Iraqi capital, Baghdad, last month, citing unspecified threats from Iran.

Last Thursday, two explosions occurred on oil tankers in the Gulf of Oman. Four oil vessels were targeted in May, also near the Strait of Hormuz - a key transit route for oil and gas from the Middle East.

It remains unclear who was responsible for the blasts. US officials have pointed a finger at Iran, which has denied all accusations. 

On Tuesday, a rocket landed near an Iraqi military base hosting US forces in the northern city of Mosul, an Iraqi military statement said.

Three rockets hit another base hosting US troops north of Baghdad on Monday. There was no immediate claim of responsibility. 

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Al Jazeera

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• Iraq
• Basra
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