An image from Google Maps shows the Amazon fulfillment center at 8003 Industrial Hwy, Carteret, NJ.

Employees at an Amazon facility in Carteret, New Jersey, were evacuated Monday as authorities investigate a threat.

The Middlesex County Sheriff's Department is at the scene with bomb-sniffing K-9s. It's unclear what prompted authorities to evacuate the facility.

"As a purely precautionary measure, law enforcement authorities have evacuated the Amazon facility off of [New Jersey Turnpike] exit 12 on Industrial Highway in Carteret's industrial district after they received a threat," Carteret Police Chief Dennis McFadden told WNBC.

An Amazon spokesperson confirmed to CNBC that the fulfillment center was evacuated earlier on Monday.

"Today, out of an abundance of caution, our Carteret fulfillment center was evacuated following a potential threat," the spokesperson said. "We take the safety of our employees and buildings seriously and are working closely with local law enforcement on their investigation."

The FBI office in Newark referred questions to local authorities.

The 1 million-square-foot center, launched in 2015, has thousands of employees who fulfill orders for residents in nearby areas. It's one of several fulfillment centers run by Amazon in New Jersey.

-- CNBC's Amanda Lasky contributed to this report.