A security guard who was killed Monday in a shooting at the Islamic Center of San Diego has been hailed as a hero for his courage during the attack. Three men were killed, including the security guard, but police said the tragedy, which is being investigated as a hate crime, could have been much worse without his intervention.

None of the victims have been identified, nor have either of the two suspected gunmen, who were found dead inside a vehicle near the Islamic Center after the shooting. People who knew the security guard have spoken out about his life, describing him as a father of eight and remembering him for his kindness and valor.

"Because of his heroism and his courage, his bravery, and the love for his community and his faith, he saved a lot of lives," said Mayte Gutierrez, a former employee of the Islamic Center's school, which is attached to the mosque. Gutierrez told "CBS Mornings" on Tuesday that she knew the security guard well.

Many have praised the guard for keeping the gunmen away from the school when they targeted the Islamic Center on Monday morning. Its imam, Taha Hassane, confirmed the entire school was safe, including all of the children and teachers, in a social media post shared in the hours after news of the shooting first broke. He later urged the public to respect the privacy of the victims and their families, while speaking at a news conference.

San Diego Police Chief Scott Wahl credited the security guard for helping contain the situation before authorities responded to the scene.

"I think it's fair to say his actions were heroic, and, undoubtedly, he saved lives today," Wahl said.

Sam Hamideh, a parent who said he knew the security guard through the Islamic Center, told CBS News Los Angeles that the man's benevolence and generosity were character traits of his that really stood out.

"This guy, like, it didn't matter who walked up ... any random person could just walk up and, like, he would greet them, make sure they are OK," Hamideh recalled. "Whether they were homeless off the street looking for something, whether it was a child or the elderly."

Wahl said at a news conference Monday that all three of the shooting victims were seen in front of the mosque when police arrived. Moments later, officers were called to a different location nearby and discovered the two suspected shooters deceased inside a vehicle, according to the police chief. The FBI said both suspects were teenagers.

Federal investigators said Monday that they had not yet determined a motive for the attack, but Wahl told reporters that "because of the Islamic Center location, we are considering this a hate crime until it's not."

The deadly shooting comes as places of worship, in the United States and internationally, are increasingly targeted in acts of violence. On Monday, San Diego Mayor Todd Gloria said more police officers would be deployed to guard places of worship to ensure "that we anticipate and try to prevent the very worst," as he also thanked the security guard for his actions at the Islamic Center.

"We didn't meet that mark today, but I have deep gratitude to the security officer who was here, whose actions and heroism undoubtedly saved lives," Gloria said.