WASHINGTON (Reuters) -- U.S. Homeland Security Secretary Jeh Johnson said on Monday that he would soon announce changes to the national alert system to warn the public about terrorism risks.
The changes come amid fresh concerns about terrorism in the United States after last Wednesday's shooting in San Bernardino, California, although they were not specifically prompted by it. President Barack Obama has called the shooting, in which 14 people were killed, an act of terrorism.
Johnson proposed revising the alert system after five U.S. service members in Chattanooga, Tennessee, were killed in July in a shooting that has also been investigated as terrorism.
See photos of the Chattanooga shooting below:
"We need to get ... to a new system with an intermediate level," Johnson said at a security forum on Monday, adding he planned to outline specific changes in the coming days.
The National Terrorism Advisory System is triggered by specific, credible information on a possible threat. The NTAS in 2011 replaced a color-coded alert system, but Johnson said more changes were needed.
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Johnson said the NTAS system had such a high bar for alerts that the government never used it. Security officials need to do a better job of informing the public about global terrorist threats and providing guidance, he added.
A DHS official said later that the move will involve changes to the existing NTAS system but not be a new system.
Related: See inside the San Bernardino suspects' apartment:
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