Updated

A law enforcement bulletin obtained by FoxNews.com warned that Islamic State fighters have increased calls for "lone wolves" to attack U.S. soldiers in America in recent months, citing one tweet that called for jihadists to find service members' addresses online and then "show up and slaughter them."

There will be “a continued call - by Western fighters in Syria and terrorist organizations - for lone offender attacks against U.S. military facilities and personnel,” warned a July law enforcement intelligence bulletin from the Central Florida Intelligence Exchange, a state-run agency that gathers, assesses and shares threat information and works with the Department of Homeland Security. “These threats will most likely increase should the U.S. or its allies attack the Islamic State of Iraq and Sham (ISIS) in Syria or Iraq.”

In one example cited in the bulletin, a British jihadist encouraged radicals still living in the West to use Facebook and LinkedIn to find and target soldiers.

"You could literally search for soldiers, find their town, photos of them, look for address in Yellowbook or something," the tweet read. "Then show up and slaughter them.”

On Thursday, Peter Boogaard, a spokesman for the Department of Homeland Security, told FoxNews.com that "there is no credible intelligence at this time to suggest that there is an active plot by (ISIS) to carry out an attack in the United States."

"Public postings by people claiming to be (ISIS) supporters on social media threatening to carry out attacks against the United States and our allies have been made, and we are aware of them," Boogaard said in a statement. "The product referenced is based on such open source social media reports from earlier this summer and is not considered to reference specific, credible evidence of a plot against the homeland.”

The bulletin came out long before Tuesday's indictment of an upstate New York man on a raft of terror-related charges, including attempting to kill "officers and employees of the United States. Mufid Elfgeeh, 30, of Rochester, was indicted Tuesday by a federal grand jury on three counts of attempting to provide material support and resources to Islamic State. Elfgeeh was arrested in late May in a Walmart parking lot after a sting in which an FBI informant offered to sell him guns and silencers, which Elfgeeh allegedly wanted to use to kill returning American troops as well as Shiite Muslims living in the region.

Killing U.S. troops on American soil is an increasing focus of jihadists, according to the bulletin, titled “Continued Threat to Military Personnel from Al Qaeda Inspired Homegrown Violent Extremists.” It was sent out on July 8, 2014, “in response to recent social media messaging from Western fighters in Syria calling for attacks against “soldiers in the West.” Instead of luring radicalized Americans to the Middle East, Islamic State will likely encourage them to stay home and kill U.S. soldiers here, the bulletin warned.

“U.S.-based [Home-Grown Violent Extremists] could be inspired by this rhetoric to turn their attention towards carrying out attacks at home,” the bulletin states.

The radical rhetoric is delivered via social media, where Islamic State operatives have long exhorted westerners to get on a plane and come join the battle. But terrorists now believe they can have a powerful effect from afar just by inspiring attacks inside the U.S.

“In recent Twitter posts, foreign fighters in Syria have encouraged Muslims in the West to target soldiers with spontaneous attacks using small arms (i.e. knives and guns),” the bulletin said.

It listed several examples of tweets posted in late June that specifically mention interest in attacking Western military personnel. In one series of tweets a British fighter formerly with Jabhat al Nusra lamented the terrorist infighting between Islamic State and groups affiliated with Al Qaeda.

"I’m realizing bickering about internal politics is taking up our time too much, the enemies are working what’s stopping you from something like learning how to make explosives or learning shooting, or killing vulnerable soldiers right now? (To the bros in the West).”

The bulletin also cited an uptick in chatter on Internet forums calling for attacks on Western military targets, with many referring to Fort Hood shooter Nidal Hassan, who killed 13 service members at the Texas Army base in 2009 in a case the Obama administration still labels as an example of "workplace violence," and not terrorism. Hasan recently announced from prison, where he is awaiting execution, he wanted to join Islamic State.

A commenter on the Ansar Al-Mujahideen English Forum reposted a 2009 statement from radicalized American Adam Gadahn, now a senior Al Qaeda leader, praising  Hasan.

"The Mujahid brother Nidal Hasan, lightly armed but with a big heart, a strong will and a confident step, again brought into focus the weaknesses and vulnerabilities of America ... and most significantly, the Mujahid brother Nidal Hasan is a pioneer, a trailblazer and a role model who has opened the door, lit a path and shown the way forward for every Muslim among the unbelievers and yearns to discharge his duty to Allah and play a part in the defense of Islam and Muslims against the savage, heartless and bloody Zionist Crusader assault on our religion, sacred places and homelands,” read the statement.

The intelligence center assessed in July “ “that military personnel will likely be targeted individually in spontaneous ‘ambush’ style attacks similar to the May, 2013, machete attack against British soldier Drummer Lee Rigby in the U.K.