Alleged Chattanooga Shooter's Friend Reveals 'War' Text Message Sent Just Before Attack

A friend of Muhammad Youssef Abdulazeez, the man alleged to have shot and killed four Marines and a Navy sailor in Chattanooga on Thursday, has said that hours before the attack he received a text message from him linking to an Islamic verse referring to declaring war, as his family has broken their silence with a statement that he had "suffered from depression" for years.

Abdulazeez's family made their first public statement days after Abdulazeez, 24, allegedly shot and killed the four Marines in an attack on a military recruitment center and Navy reserve center in Chattanooga, Tennessee before he was killed by police.

On Saturday, authorities announced that a fifth victim, a Navy sailor, died from injuries he sustained in the attack on Thursday.

Authorities have said they are looking into the incident as an act of domestic terrorism, but have not released information about a suspected motive. Abdulazeez reportedly sent a text to a friend hours before the deadly shooting that linked to an Islamic verse containing alarming language, according to Reuters. The text included the phrase, "Whosoever shows enmity to a friend of Mine, then I have declared war against him."

"I didn't see it as a hint at the time, but it may have been his way of telling me something," the friend, who asked to remain anonymous, told Reuters.

As speculation about Abdulazeez's motives has intensified, his family released the statement through their lawyer decrying his actions, and said they are cooperating with authorities in their investigation.

"There are no words to describe our shock, horror, and grief," the family said. "The person who committed this horrible crime was not the son we knew and loved. For many years, our son suffered from depression. It grieves us beyond belief to know that his pain found its expression in this heinous act of violence."

"We understand there are many legitimate questions that need to be answered," the statement says. "Having said this, now is the time to reflect on the victims and their families, and we feel it would be inappropriate to say anything more other than that we are truly sorry for their loss."

Related: Chattanooga Shooting Being Investigated As Domestic Act of Terrorism

The announcement that the shootings are being investigated as a potential case of domestic terrorism comes amid fears that propaganda from the self-proclaimed Islamic State could inspire "lone wolf" attacks in the US. Earlier this week, Kuwaiti officials said that Abdulazeez had been in Jordan and Kuwait in 2010, according to CNN. He had also been in Kuwait again as recently as 2014 to visit an uncle, CNN reported. The FBI and US Department of Homeland Security issued an intelligence bulletin Friday warning of potential lone wolf-style attacks.

After FBI officials visited Abdulazeez's family home following the attack on Thursday, two women in headscarves were seen leaving the home in handcuffs, according to the AP. However, FBI officials said that no further arrests have been made in the case.

Friends of the family told reporters that the family felt blindsided by the shooting.

Bassam Issa, the president of the Islamic Society of Greater Chattanooga, told the AP that Abdulazeez's father told him did not see any recent changes in his son.

"He told me that he had never seen it coming, and did not see any signs from his son that he would be that way and do something like that," he said.

Issa told the Chattanooga Times Free Press that the alleged shooter's father was crying and distraught during the call.

"He said he was very sorry for what his son did," he said. "He knows that his son has done so much harm to Chattanooga and to those families. This boy has destroyed his family forever."

Related: Man Convicted of Terror Plot in Canada is 'Delusional' Says Doctor

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