Shootings at a pair of military facilities in Chattanooga, Tenn., Thursday, left five people dead, including four Marines and the lone gunman, officials said.
The shooter was later identified by the FBI as 24-year-old Mohammod Youssuf Abdulazeez, and it was revealed late Thursday by SITE, a widely read website that tracks Islamic terrorism, that he maintained a blog where he wrote “Islamic-focused” posts that were entered as recently as three days ago.
An FBI official told Yahoo News, "there is no reason to question the authenticity" of the blog with the pro-jihad entries. The official said it is actively investigating whether the shooter may have contacts with ISIS through social media, but currently has no evidence of that.
In a July 13 post, Abdulazeez wrote that “life is short and bitter” and that Muslims should not let “the oppourtunity to submit to Allah…pass you by,” the website said in an email sent to subscribers.
He also stressed the sacrifice of the Sahaba [companions of the Prophet] with mention that, "Every one of them fought Jihad for the sake of Allah. Every one of them had to make sacrifices in their lives and some even left all their wealth to make hijrah to Medina,” he wrote, according to SITE.
A U.S. official told the Associated Press that Abdulazeez had not been on the radar of federal law enforecment before Thursday's shooting. His father had been investigated several years ago for "possible ties to a foreign terrorist organization" and added to the U.S. terrorist watch list, according to a report in the New York Times, but that probe did not surface information about Abdulazeez, the paper said.
Late Thursday night in a Chattanooga press conference, FBI officials maintained that there is no threat to the general public following the shooting, which left local officials and residents reeling.
"It is incomprehensible to see what happened," Mayor Andy Berke said at a news conference Thursday afternoon. "This is a nightmare for the city of Chattanooga."
Three other people, including a Chattanooga police officer, were wounded in the shootings, Berke said. They were transported to local hospitals with non-life-threatening injuries.
The shootings began shortly after 10:30 a.m. at a National Guard office in a strip mall on Lee Highway, where the suspect fired from his car, aid the FBI. A witness there described hearing as many as 20 shots fired there before the gunman fled. A photo posted to Facebook by a witness shows the door of the office littered with bullet holes.
Police say Abdulazeez then drove to the Chattanooga naval reserve center, where a witness told CNN she saw a man with "a high-powered rifle" fire multiple shots from a convertible silver Mustang into recruiting offices at the center shortly before 11 a.m. ET.
Four U.S. Marines were killed at the naval center. Their names have yet to be released.
Abdulazeez was killed at the scene. Ed Reinhold, special agent in charge of the FBI's Knoxville field office, said late Thursday night that Abdulazeez got out of his car before killing the Marines.
"Somebody brutally and brazenly attacked members of our armed forces," Chattanooga Police Chief Fred Fletcher said at the afternoon news conference.
Because the shootings occurred at U.S. military facilities, the FBI is leading the investigation.
U.S. District Attorney William C. Killian said officials were treating the shootings "as an act of domestic terrorism."
Reinhold said at that point there is no evidence to suggest it was, a view he repeated late Thursday night. He declined to speculate on a motive.
Following the Thursday afternoon press conference, law enforcement swarmed a house believed to belong to Abdulazeez, according to the Associated Press. An reporter "saw officers with weapons drawn at the house and two females were led away in handcuffs." It's not clear who these females are.
According to the Times Free Press, Adbulazeer was arrested on a DUI charge on April 20, 2015.
At the White House, President Barack Obama called the shootings "tragic."
Obama offered "the deepest sympathies of the American people" to the victims' families.
"I'd ask all Americans to pray for the families that are grief stricken," the president said.
Officials said "several weapons" were recovered at the second scene. An image showing the vehicle police say the suspect was driving was broadcast by WTVF-TV.
As news of the shootings broke, Berke cut short a news conference at City Hall.
"This is a very, very terrible situation," he told reporters. "I'm very concerned about what's going on. We need to figure out how to handle it."
Hospitals, businesses and the nearby Chattanooga State Community College were placed on lockdown.
Early Thursday afternoon, the Chattanooga Police Department announced via Twitter that the active shooter situation was over.
The incident in Chattanooga bore some semblance to a 2009 shooting in Little Rock, Ark., where 24-year-old Abdulhakim Mujahid Muhammad drove to a military recruiting station and opened fire, killing one U.S. Army officer and leaving another wounded. Muhammad later confessed to the killing and received several life sentences after pleading guilty to capital murder and attempted capital murder. Muhammad cited religious reasons to justify his acts, but officials could not find proof of any links to a terrorist organization.
Thursday's shootings also occurred less than two years after the September 2013 massacre at the Washington Navy Yard, where a lone gunman killed 12 people in the second-deadliest attack on a military base in U.S. history.
The gunman in that attack, Aaron Alexis, was a former Navy petty officer third class who had been honorably discharged two and a half years prior to the shooting.
Earlier this month, authorities investigated another possible shooting at the Navy Yard after an employee reported hearing possible gunfire. The base was later declared all clear.
— Yahoo News Chief Investigative Correspondent Michael Isikoff (@Isikoff) and Sean Billings contributed reporting to this article, which has been updated since its initial publication.