(Cnn) FBI: Afghan civilian killings could spark attacks in U.S.

Washington (CNN) -- The alleged murder of 16 Afghan civilians by a U.S. soldier could spur retaliatory violence in the United States, a law enforcement advisory by the FBI and Department of Homeland Security warned.

The intelligence bulletin, which was issued Wednesday to state and local law enforcement partners, says "there is currently no specific, credible threat information" that extremists might strike targets in the United States.

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However, the document, which was obtained by CNN, notes the March 11 killings of the Afghans is the latest in a series of events in Afghanistan that could cause anger and possibly lead to violent action.

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"The FBI and DHS are concerned that this event could contribute to the radicalization or mobilization of homegrown violent extremists in the Homeland, particularly against U.S.-based military targets," the bulletin said.

The document notes that the soldier suspected of committing the killings is based at Joint Base Lewis-McChord near Tacoma, Washington, and states that in the past, extremists have viewed military sites as "legitimate targets for retaliation in response to past alleged U.S. military actions against civilians overseas."

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The law enforcement advisory also lists other recent events in Afghanistan that could incite violence in the United States, including the February burning of Qurans and other religious texts by U.S. soldiers in Afghanistan and a video that surfaced in January which appeared to show U.S. Marines urinating on the bodies of Taliban fighters.

The Quran burning sparked protests that left as many as 40 people dead, including six U.S. servicemembers.

U.S. officials also have promised a full investigation into the deaths of the 16 civilians.

According to the bulletin, it's unlikely that any one of these events alone would lead to violence in the United States, but it noted they will be used in "violent extremist propaganda and could contribute to an individual's radicalization to violence."

The FBI and DHS called on local law enforcement to be vigilant for possible violence, particularly against U.S. military targets