Wahl described the scene as “extremely chaotic”, saying that somewhere between 50 to 100 police officers responded to the scene. Officers, he said, observed the three deceased victims upon arriving.
FBI special agent Mark Brimley, of the bureau’s San Diego field office, told reporters the bureau was investigating a motive, and that it was “meticulously assessing the situation and is prepared to employ every resource we have to uncover the facts of this incident”.
He urged the public to share any information that could be useful in the investigation and said that the FBI had set up a digital media tip line.
He added: “No community should have to go through such a tragic incident, but we will work tirelessly until we learn the truth. We have on scene a number of special agents, task force officers or evidence response personnel, victim specialists and many more.”
The Islamic Centre describes itself online as the largest mosque in San Diego, and it serves as both a religious institution and a school.
Imam Taha Hassane, the centre’s director, told reporters that the center had “never experienced a tragedy like this before”.
He said: “It is extremely outrageous to target a place of worship. People come to the Islamic Centre to pray, to celebrate, to learn. Not only Muslims but we have people from all walks of life.”
Hassane said that all children, staff and teachers were safe and had been evacuated from the building.
The shooting occurred on the first day of Dhul Hijjah, one of the most sacred periods in the Islamic year.
The Islamic Centre is also minutes away from an elementary school and a charter school, and it is in the neighbourhood of Clairemont Mesa East, a heavily residential area close to the beach.
Speaking to reporters, San Diego Mayor Todd Gloria said he wanted to reassure San Diego’s Muslim community that “we will do everything it takes to make sure that you can feel safe in this city”.
US President Donald Trump described the shooting as a “terrible situation”. telling reporters: “At the mosque, they’re giving a briefing. It’s a terrible situation. I’ve been given some early updates but we’re going to be going back and looking at it very strongly.”