One person is in custody following a small explosion at the Sam’s Club in Ontario caused the store to be evacuated Thursday afternoon, police said.

What was first reported as a structure fire at the 951 North Milliken Ave. store was actually determined to be a small explosion after a person detonated a device inside the store, the Ontario Police Department said in a news release.

“There appears to be no structural damage or any injuries at this point,” the Police Department said in the statement. “All employees and customers are accounted for.”

Police work the scene on Airport Dr. after a suspect involved in the Sam’s Club incident was detained near Etiwanda Ave. and Airport Dr. on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

The Sam’s Club in Ontario was evacuated after a device was detonated early afternoon on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

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Airport Dr. was shut down for several blocks after a suspect involved in the Sam’s Club incident was detained near Etiwanda Ave. and Airport Dr. on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

The Sam’s Club in Ontario was evacuated after a device was detonated early afternoon on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

A Sam’s Club employee speaks to an officer after the store was evacuated when a device was detonated early afternoon on Thursday, April 5, 2018 in Ontario. (Stan Lim, Inland Valley Daily Bulletin/SCNG)



The Sam’s Club in Ontario was evacuated after a device was detonated early afternoon on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

The Sam’s Club in Ontario was evacuated after a device was detonated early afternoon on Thursday, April 5, 2018. (Stan Lim, Inland Valley Daily Bulletin/SCNG)

John Anthony, of Fontana, said he was at Sam’s Club about 3 minutes after the explosion. He saw a “massive” response from police and fire personnel, an estimated several dozen police and fire vehicles.

Anthony saw people leaving the store after the blast. “They were pretty calm. Some people were running,” he said.

A Sam’s Club manager at the location directed questions to corporate media relations.

The initial call came in shortly after 2 p.m. that a explosion went off inside Sam’s Club, police said. Both police and fire officials responded to the scene and located a destructive device inside the store.

Police Chief Derek Williams said a “small destructive device” went off in Aisle 4 inside the store.

Williams said it was “tremendously lucky” that no one was hurt. He said it will take “a little while” before police can clear the area.

Police and Bureau of Alcohol, Tobacco, Firearms and Explosives agents remained on scene into the evening to search the store and interview witnesses.

While at the store, police received information that helped them locate a suspect vehicle and a short pursuit ensued, officials said.

One person was detained a short distance from the Sam’s Club, according to Officer Elisio Guerrero, a spokesperson for the Ontario Police Department. Another device was found inside the vehicle near Airport Drive and Etiwanda Avenue, officials said.

Police believe that suspect Hugo Gonzalez, 49, of Fontana, acted alone, but a motive wasn’t immediately clear.

“Within the vehicle Gonzalez was driving, investigators located additional materials similar to those used in the devices” found in the store,” the Ontario Police Department tweeted just before 6:30 p.m. “Police are currently at an apartment in the 16500 block on Arrow Blvd. in Fontana, which is believed to be associated with Gonzalez.”

Ontario police obtained a warrant, and the ATF, Inland Valley SWAT team and the county’s bomb squad searched two or three apartments and no further devices were found.

The apartment complex and the area around it were evacuated with the assistance of the Fontana Police Department. Arrow was also closed between Juniper and Cypress avenues.

“Our officers, the bomb squad, and our SWAT team have made entry into the residences in question. They were deemed safe and secure,” said Fontana Officer Jay Sayegh.

Other people were inside the two or three residences when officers arrived, and they were cooperative and came out, Sayegh said. It’s unclear how many people were inside and what connection they have, if any, to the suspect.

Inland Valley SWAT team and the bomb squad are now searching a Fontana apartment, at 16550 Arrow Blvd., which is associated with the suspect. pic.twitter.com/Q3k2iuCJP1 — Mike Cruz (@mikecnews) April 6, 2018

Sayegh said the suspect does live at the apartment complex. But it’s unknown for how long.

There was no word whether any other weapons or evidence was recovered from the apartments.

Sayegh said officers who made entry into the apartments were unsure of what they were dealing with and didn’t know the suspect’s expertise level.

“It’s a very delicate situation. You have to be very careful,” Sayegh said.