Police discovered a bomb in the gymnasium of a Petah Tikva middle school Tuesday night and arrested the school's custodian early Wednesday.
The custodian, who is responsible for the gym where the bomb was found, is suspected of trafficking in weapons and drugs.
Petah Tikva Mayor Itzik Braverman said police told him the school was not the target of the bomb.
Police said the raid kept students and teachers from exposure to "serious danger."
"The immediate and decisive activity of the [Lahav 433 police] unit prevented a serious danger to the students and staff of the school, who were in a school where an explosive device was held, without their knowledge," the police said in a statement.
The custodian is one of two Petah Tikva residents, both 31, arrested Wednesday, in possession of the bomb and what appears to be drugs. The second man is suspected of attempted drug trafficking.
Police raided the school after receiving a tip informing them that an explosive device ready to be activated was being stored in the school, located on Ir Ganim Street. They had already been investigating the weapons trafficking for several weeks but only found out about the bomb Tuesday, said the commander of the police's Central District, Bruno Stein.
"Dozens of sappers and police officers combed through the school and the classrooms overnight," Stein told Army Radio.
He said additional arrests were expected in the coming days.
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