'Suspicious' Aliso Viejo Explosion Kills 1, Triggers Evacuations

ALISO VIEJO, CA — A woman was killed and at least three others were injured in an explosion and fire at an Aliso Viejo outpatient mental health clinic Tuesday afternoon. As of 8 p.m. it remains unclear whether the explosion that obliterated the corner of the 11 Mareblu building was intentional in nature. NBC and the Los Angeles Times, citing unnamed sources, is reporting that the explosion was considered intentional, resulting from an explosive device delivered to the building.

Authorities Tuesday night were calling the explosion suspicious, adding they did not believe there is any ongoing threat to the community.

The explosion triggered evacuations and chaos amid unconfirmed reports regarding the cause of the blast. FBI Special Agent in Charge DeLacourt revealed that the motivation behind the explosion doesn't change the response that is brought to to bear after the initial clearance. "A thorough and methodical search of the scene will take place," he said.

The area is likely to remain closed to traffic, for the next 24-hours at least, according to reports.

"We're going to find out exactly what happened and let the truth come out," Orange County Sheriff's Cmdr. Dave Sawyer said. He would not officially confirm what sort of device had been found, if it was a bomb or something else, in the last briefing of the day. He said investigators had not found an explosive device at the scene.

Homeland Security and the Bureau of Alcohol, Tobacco and Firearms are also assisting in the investigation, according to Orange County Sheriff's Department. No arrests have been made and no suspects have been identified as of this report.

The massive massive deployment of law enforcement officers including a bomb squad continued to work to clear the scene after the initial explosion at 1:15 p.m. It was several hours before a plan was put into place to enter the facility to determine if there were explosive devices inside. Bomb sniffing dogs were deployed before officers enter the building, authorities said.

"We are going to take every precaution necessary before we enter that building," said Orange County Fire Authority Capt. Tony Bommarito.

Following the explosion, victims covered in blood and ash were seen helping one another from the building.

"The only thing we know for sure right now is that it was an explosion," an OCSD spokesperson said.

Earlier reports of a car crashing into the building have been refuted, according to Orange County Sheriff's Department spokeswoman Carrie Braun. According to CBS2, Orange County Sheriff's deputies are taking photographs of all vehicles leaving the area. The blast comes a day after sheriff's deputies were called to the same block of Mareblu at for a "patrol check,'' according to sheriff's records. It was not immediately clear what prompted that call.

"OCSD will not confirm the cause of the blast," spokeswoman Carrie Braun told Patch. Officers will remain on the scene trying to determine exactly what happened, Braun said.

The FBI has sent resources to help with the investigation, which is being led by Orange County Sheriff's Department. Officials say that there does not appear to be any further threat to the community.

As of this report, it is unknown if the person who died inside was a man or a woman.

According to Orange County Fire Authority's Bommarito, one of the injured people suffered smoke inhalation. Both that patient and two others were transported to area hospitals. However, the extent of the other victims' injuries was not known as of this report.

Witnesses to the fire told CBS2 that victims of the blast who fled the structure were "helping each other across the street, walking slowly, a lot of shock and shaking," an unnamed woman said, adding the victims were "full of ash all over their face, eyes bloodshot, just blood all over."

Meanwhile, Children from Academy on the Hills preschool across the street from the building were not endangered in that explosion, and no children were injured, according to reports. At 2:30 p.m. OCFA helped mothers and kids evacuate the daycare facility and are taking the children to a nearby Target parking area to be reunited with their families on 26932 La Paz Road.

OCFA and OCSD officers are investigating all possible hazards from this incident.

Witness Doug Shin told Patch his thoughts about the scene.

"People were really scared," he said. "There were two holes with fire coming out of either side, and there was insulation coming out. Firefighters arrived within five minutes."

The Aliso Viejo Police Services have closed roads in the area of Oso and Moulton parkways and La Paz Road. Drivers are asked to avoid the area.

Anyone with info about Aliso Viejo explosion is asked to call OC sheriff’s dept at (714)647-7000.

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