(SANTA MONICA, Calif.) -- The California man who shot to death five people in Santa Monica last week, including his father and brother, left a farewell note expressing remorse for his actions, police say.
Police discovered the handwritten note, which they said was three to four pages long, on the body of John Zawahri, 23, after he was shot and killed by police inside the Santa Monica College library.
"We know that he left behind what can be called a farewell note in which he expressed hope that his mother would be looked after financially, even as he said goodbye to his friends and expressed remorse for his actions and the killing of his brother and his father," said Santa Monica Police Chief Jacqueline Seabrooks at a news conference.
Police only on Thursday announced the discovery of the note, the text of which has not yet been made public.
The note did not provide any explanation for the 13-minute shooting spree that claimed the lives of three additional victims after Zawahri shot killed his father and brother in their family home, then set the house ablaze.
Shortly after setting fire to the family home, Zawahri fled on foot through the streets of Santa Monica, eventually carjacking a woman whom he directed to drive him to the Santa Monica College campus, stopping en route to fire indiscriminately on unarmed civilians and vehicles.
Police believe "mental health challenges," are partly responsible for the rampage.
"We know his was a troubled life and that he experienced mental health challenges," Seabrooks said. "We believe that his mental health challenges likely played a role in his decisions to shoot and kill both his father and brother, to set fire to the family home and to go on a 13-minute shooting spree spanning roughly 1.5 miles and which left five innocent people dead and three people injured."
Zawahri assembled his own .223-caliber assault rifle that he used to shoot his father and brother. He fired approximately 100 rounds of ammunition during the rampage, but was carrying 1,300 rounds in high-capacity magazines capable of holding 30 rounds each.
The high-capacity magazines found on Zawahri are illegal to purchase, sell or transfer in California, though possession is not illegal.
Police also say they found replica weapons and zipguns (improvised firearms) during a search of Zawahri's house.
Zawahri's mother, Randa Abdou, who is mentioned in the farewell letter, issued a statement requesting privacy earlier this week.
"As may be assumed, I am in mourning for my family and for those who were also affected by this horrific tragedy over the past few days. I cannot express my great sadness for the families who are also suffering at this terrible time," the statement read.
"I do ask the media please give me time to grieve and to come to grips with the overwhelming sorrow that has befallen all of us," the statement concluded.
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