RIYADH, July 20: Saudi security forces have uncovered a militant hideout filled with bomb-making materials south of the capital Riyadh, the interior ministry said on Wednesday.

It said the cache included two tons of fertilizer, ammonium nitrate, aluminium powder, potassium nitrate and other chemicals used by suspected Al Qaeda militants to make bombs in their two-year wave of attacks against Saudi Arabia.

Security forces who searched the hideout on Tuesday in Kharj, 60kms southeast of Riyadh, also found pipe bombs, acid and electrical equipment, the ministry said in a statement.

The statement came hours after the US embassy in Riyadh warned its citizens in Saudi Arabia that militants were planning fresh strikes in the world’s biggest oil exporter.

Saudi Arabia has been battling a wave of violence by supporters of Saudi-born Osama bin Laden’s Al Qaeda network.

US embassy: A statement issued by the US embassy in Riyadh said it had no specific details about possible targets or timing of attacks but advised Americans to keep a low profile.

Saudi officials were not immediately available to comment on the warning, but one security source said several previous alerts by Western missions had proven unfounded.

“The American embassy in Riyadh advises all American citizens living in Saudi Arabia that it has received indications of operational planning for a terrorist attack or attacks in the kingdom,” an embassy statement read out by an official said.—Reuters