JERUSALEM — Egypt’s gas pipeline to Israel was attacked for the 13th time in a year.

Monday’s explosion west of El Arish in the northern Sinai Peninsula came after masked gunmen attacked the pipeline, Reuters reported.

The extent of the damage is unclear, according to the Associated Press. Previous attacks have left the pipeline unusable for weeks and months at a time.

An attack on Feb. 5 shut down the pipeline, and since then has not not resumed operation.

The supply of gas to Israel has been halted numerous times in the last year, leading to a scramble to find alternate fuel sources to produce electricity that are more expensive.

Egypt supplies Israel with more than 40 percent of its natural gas needs to produce electricity; electricity prices have risen by more than 10 percent in Israel since the attacks began.

The first attack on the pipeline came in February 2011 during uprisings against Egyptian President Hosni Mubarak, who was deposed.

Selling gas to Israel has been unpopular on the Egyptian street since the opening of the pipeline in 2008. Mubarak has been accused of giving Israel a sweetheart deal on the gas, since Egypt lost more than $714 million on the pact.