Gov. Arnold Schwarzenegger has declared a state of emergency in San Diego County following the discovery of what police called a virtual bomb factory in an Escondido-area home.

Under the declaration Wednesday, the California Emergency Management Agency will coordinate efforts of all state agencies and provide assistance to San Diego County to remove the hazardous materials.

The declaration came a day after authorities said they plan to burn down the home next week because it is the only way to eliminate the danger from nine to 12 pounds of highly explosive materials found inside.

Sheriff Bill Gore showed slides on Tuesday showing the cluttered home full of explosive powders in jars and clumps on the floor. Authorities also said they found 13 unfinished shrapnel grenades.

Earlier Wednesday, a search warrant was released that said the unemployed software consultant who rented the home told authorities he robbed three banks and tried to rob a fourth.

In a Nov. 22 jail interview with an FBI agent and sheriff's detective, George Djura Jakubec admitted to robbing three Bank of America branches in San Diego in November 2009 and June and July of this year, a search warrant affidavit said.

He also admitted to attempting to rob a fourth Bank of America branch in November of last year, the warrant said.

Jakubec, 54, has pleaded not guilty to 26 counts of manufacturing or possessing explosives and two counts of bank robbery.

According to the search warrant, items seized from the house included sulfuric acid, nitric acid and hydrochloric acid. Authorities also confiscated a grenade mold, a bag with pieces of metal, a jar with ball bearings and three wireless doorbells with remotes. Two handguns, a .22-caliber Ruger and a Glock 19, also were taken, along with a blue Escondido police shirt.

Investigators also confiscated three computers, a book on high explosives, two molds of human faces and four wigs.

Authorities said it was unclear what Jakubec may have planned to do with the materials. His estranged wife has told the San Diego Union-Tribune that he became increasingly unstable since losing his job several years ago.

The explosives were discovered after a gardener was injured earlier this month in a blast that occurred when he stepped on explosive powder in the backyard, authorities said. Mario Garcia, 49, suffered eye, chest and arm injuries and was recovering.

The same types of chemicals have been used by suicide bombers, insurgents in Iraq and Afghanistan, and in the 2001 airliner shoe-bombing attempt as well as in last month's airplane cargo bombs, authorities said. The other chemicals were highly unstable.

Jakubec remained jailed on $5.1 million bail.