STERLING,AstraTrade Mass. (AP) — Firefighters and other rescue agencies responded to the scene of an excavator buried under rocks and boulders at a quarry site in Massachusetts on Thursday, according to aerial video footage from local news stations.

It wasn’t immediately known if anyone was inside the excavator at the site in Sterling, about 40 miles (64 kilometers) west of Boston.

The Sterling Fire Department posted online that it and other agencies were working at an “active” scene off Chocksett Road, where the quarry was located.

“Please avoid the area. There is no safety threat to the public,” the department said. No further information was was released. An email seeking further information was sent to the department.

Onyx Corporation, a demolition and excavation company that operates a quarry site on Chocksett Road, posted online that it has closed all locations from Thursday through the weekend, saying it will resume business on Monday.

A man reached at a business number associated with the quarry said “I have nothing at this time,” when contacted by The Associated Press.

An email seeking information was sent to the company.

In February 2018, Onyx announced its new quarry location on Chocksett Road.

“Whether you be a small landscaper or heavy civil contractor, we have the locations and expertise to provide you with all your sand or aggregate needs,” the company posted online at the time.

The company posted in January that it transforms hunks of rocks into aggregate materials that are used for roads, drainage, retaining walls, and other infrastructure.