Twenty-four Amazon workers have been hospitalized after a robot accidentally tore open a can of bear repellent spray in a warehouse in New Jersey in the U.S., ABC News reported Thursday.

One Amazon employee was in critical condition while 30 others received immediate medical treatment on the scene when the accident happened Wednesday at the 1.3-million-square-foot (about 120,774 square meters) Amazon fulfillment center in the town of Robbinsville, New Jersey.

The ABC news quoted a township official as saying that the wounded workers were treated at five local hospitals. Some workers experienced breathing problems, and stinging in their throat and eyes.

"An automated machine accidentally punctured a 9-ounce bear repellent can, releasing concentrated Capsaican," John Nalbone, the Robbinsville pubic officer, told the U.S. new outlet after an official investigation.

An Amazon spokesperson said all employees in that area have been relocated to safe place, because "the safety of our employees is our top priority."

Nalbone said earlier that no threat was posed for residents in the area and the fumes containing repellent substance were confined to the third-floor south wing at the fulfillment center.

The Amazon facility in Robbinsville employs more than 3,000 workers.