CAIRO, July 30 (Reuters) - Gunmen using rocket-propelled grenades on Saturday attacked a cooling system linked to an Egyptian pipeline in Sinai that supplied gas to Israel until it was blown up earlier this month, security sources said.
It was the fifth assault this year on energy infrastructure providing Egyptian natural gas to Israel.
Saturday's attack punctured a hole in a pipeline that had been empty since it was blown up, halting its pumping operations, security sources said.
The gunmen, who were in two trucks, initially tried to storm the area's main gas station but fled when confronted by army officers. But they then targeted the pipeline from a distance using rocket-propelled grenades, witnesses said.
No casualties were reported in the incident.
Egyptian authorities have blamed unidentified "saboteurs" and "armed gangs" for the pipeline attacks.
Attacks on Egypt's energy infrastructure have escalated since President Hosni Mubarak's overthrow in February. The main target has been the North Sinai pipeline, which also supplies Jordan.
In the face of corruption accusations stemming from the alleged sale of gas to Israel at below market prices, Egypt has been trying to renegotiate gas prices with Israel and Jordan since Mubarak was toppled. Israel says it pays market rates.
Previous attacks on the pipeline on April 27 and on February 5 forced its closure for several weeks. (Reporting by Yusri Mohamed; writing by Shaimaa Fayed; editing by Mark Heinrich)