Heavily armed police officers raided a home near Chattanooga, Tennessee, Thursday, believed to belong to shooting suspect Mohammod Youssef Abdulazeez, and detained two women, as federal, state and local law enforcement scrambled to take action in the wake of a shooting that left four U.S. Marines dead. Video published by the Associated Press shows SWAT officers arriving at the home in a military-style vehicle and pointing guns at the home. It shows one woman, who appears to be wearing an Islamic headscarf, being taken away by officers in handcuffs. The other woman is not shown in the video.

At a press conference Thursday evening, Tennessee Gov. Bill Haslam said the attack was “a horrible day for Chattanooga and a tragic day for all of Tennessee,” and praised law enforcement agencies for their cooperation in the wake of the shooting.

Few details of the investigation into Thursday's shootings have been revealed. Chattanooga Police Chief Fred Fletcher refused to comment on the specifics of the investigation, telling reporters that the Department of Justice and the FBI were spearheading the effort.

Asked about the risk of a possible backlash against Muslim communities in the state, Fletcher said that law enforcement was remaining vigilant, and would deploy resources to protect communities that might feel “vulnerable.”

More also emerged late Thursday about suspected gunman Mohammod Youssef Abdulazeez, who was shot dead by police following the attack. A Kuwait-born naturalized U.S. citizen and a graduate of the University of Tennessee at Chattanooga, Abdulazeez was reportedly not under investigation by the FBI prior to the attack.

His sole brush with law enforcement thus far appears to be an April 2015 DUI arrest, for which he was scheduled to appear in court later this month, and a 2011 citation for driving without insurance and speeding, according to WRCB-TV in Chattanooga.

In a statement released Thursday, the Islamic Society of Greater Chattanooga “condemn[ed] this act in the strongest possible terms."