WASHINGTON — Federal law enforcement officials said Friday that FBI agents have secretly monitored radiation levels at mosques, businesses and homes for several years in large cities, including Los Angeles, to determine whether radioactive, or "dirty," bombs were being assembled.
The officials said no suspicious radiation levels have been found.
The disclosure, following the revelation a week ago that the government has secretly spied on U.S. citizens without court permission, angered some U.S. Muslim leaders. They cited a Supreme Court ruling three months before the Sept. 11, 2001, attacks in which the justices rejected such government monitoring.
"All Americans should be concerned about the apparent trend toward a two-tiered system of justice, with full rights for most citizens and another, diminished set for Muslims," said Nihad Awad, an official of the Council on American-Islamic Relations, the nation's largest Muslim civil liberties group.
But Justice Department officials said the monitoring was lawful. They said investigators used special equipment to gauge radiation levels at homes, businesses, warehouses and centers of some Muslim groups, and that the testing was sometimes carried out in or near parking lots and driveways -- areas the government believes to be public property. The equipment also checked for chemical weapons.
They said the testing was still taking place. It was first reported Friday by U.S. News & World Report.
"This is being done in a manner that protects U.S. constitutional rights," said Brian Roehrkasse, a Justice Department spokesman. "FBI agents do not intrude across any constitutionally protected areas without proper legal authority."
After the Sept. 11 attacks on New York and the Pentagon, federal officials began monitoring Muslim groups' activities to determine whether they were planning attacks.
They apprehended Jose Padilla, a Muslim from Chicago, as he returned to the United States, allegedly to scout out targets for a "dirty bomb."
"The U.S. government is very concerned and has been very concerned over the past three years with a growing body of sensitive reporting that continues to show Al Qaeda's clear intention to obtain and ultimately use chemical, biological, radiological, nuclear or high-energy explosives in attacks against America," Roehrkasse said.
"With this in mind, the FBI is part of an interagency team conducting passive operations in publicly accessible areas to detect the presence of radioactive materials in the air," he said.
