The recent fatal ambush of four US Marines in Chattanooga features many of the hallmarks of a lone-wolf attack directed or inspired by the Mid-east-based terror group Islamic State.
Although investigators have not found direct evidence of a link between the shooter, Muhammad Youssef Abdulazeez, and Islamic militants, federal agents are intensifying their efforts to discover who the Kuwaiti-born US citizen might have been communicating with in recent months.
His computer and cell phone are being subjected to forensic analysis. And officials are trying to piece together foreign trips Mr. Abdulazeez took to Jordan and Kuwait.
In the meantime, authorities have found no written or video-taped messages from the 24-year-old explaining the attack or pledging allegiance to Islamic leaders overseas. And there is no evidence at this point that he had a state of mind that would compel him to undertake Thursday’s deadly assault on a military recruitment office and training facility.
Neither the Islamic State group nor other militant groups have claimed responsibility or involvement in Thursday’s ambush, though many militants have hailed him on social media as a martyr.
In addition, Abdulazeez had been arrested in April by local police for driving under the influence of alcohol and, perhaps, marijuana. Personal use of alcohol and illegal drugs is inconsistent with the message of Islamic extremists, experts say.
Nonetheless, some officials say they strongly suspect that the attack was Islamic-inspired terrorism, and they are warning of the possibility of similar attacks in America in the future.
“This is the event we were worried about,” Rep. Michael McCaul, chairman of the House Homeland Security Committee, told a press conference on Friday.
“My judgment is that this was an ISIS-inspired attack,” Rep. McCaul said, using an acronym for the Islamic State group.
McCaul has chaired a series of congressional hearings in recent weeks examining attempts by Islamic militants to inspire recruits to travel to Syria to join the fight on the front lines or to remain in the US and conduct indiscriminate attacks.
Islamic State leaders have appealed for attacks to be directed against military personnel and police officers in the US. In addition, they have urged that such attacks take place during the Muslim holy month of Ramadan, which ended Thursday.
Abdulazeez’s ambush fits these characteristics. But it is also different than other attacks. For example, before carrying out a similar armed ambush against a Mohammed cartoon contest in Garland, Texas, Elton Simpson used social media to declare his allegiance to the leader of the Islamic State.
In contrast, the only online communications apparently left behind by Abdulazeez before his attacks were two recent blog posts about Islam.
In one passage he writes: “Brothers and sisters don’t be fooled by your desires, this life is short and bitter and the opportunity to submit to allah may pass you by.”
Although some analysts see in such writings a fatal hint, the blog posts are nothing close to the usual fiery exhortations of extremists seeking martyrdom.
It is unclear whether family members sensed a change in Abdulazeez in recent months or weeks. But those who knew him in the community said the violent actions did not fit with their view of his personality.
One recent change that some analysts have noted: he had grown a beard, which is common among devout Muslims – and extremists.
Analysts also point to the timing of the attacks and the choice of military targets to strongly suspect an Islamic connection.
The Chattanooga attacks come at time of escalating activity among individuals in the US inspired by Islamic extremism. There were 19 IS-linked plots in all of 2014, according to statistics maintained by the House Homeland Security Committee. So far in 2015, there have been 29 such plots.
There are roughly 4,000 westerners who have traveled to Syria to join jihadist groups on the front lines, 200 of them are Americans. Of those, some 40 are believed to have returned to the US.
But that isn’t the only threat of radicalization posed by such groups, experts say. The Islamic State has refined to an art the ability to reach out to certain vulnerable or receptive individuals in the US and recruit them to a jihadist cause that seeks to justify beheadings and sexual slavery on religious grounds.
Evidence of this radicalization is illustrated in the growing number of criminal cases filed against individuals trying to travel to Syria or plotting to conduct violent acts in the US.
So far this year, 60 individuals have been arrested for plotting to provide support to Islamic extremists or conduct attacks on their behalf. The FBI has acknowledged that there are IS-related investigations underway in all 50 states.
In a press conference on Friday, officials involved in the investigation said the case was in its early stages and that it was premature to speculate about a motive for Abdulazeez’s actions.
“At this time we have no indication that he was inspired by or directed by anyone other than himself,” Ed Reinhold, the top FBI official in Chattanooga, told reporters.
He said investigators have covered 70 leads so far.
Officials note that one of the most chilling aspects of the attack is that it was launched by someone who was apparently completely off the radar of counterterrorism officials.
“What happened yesterday unfortunately could happen any time, any place in this current threat environment,” Rep. McCaul said.
He said the Islamic State group represents a new generation of terrorists who are able to reach out and radicalize certain individuals wherever they are in the world – including in the US.
The IS recruitment network is capable of producing 200,000 tweets on Twitter per day. “The volume of chatter is so high and so intense that it is hard to get a handle on it,” McCaul said.
He noted that IS recruiters and facilitators initiate contacts on open-source social media sites like Twitter and Facebook. But then they direct the communication to an encrypted platform where intelligence officials are unable to break the code and monitor the contact.