A broken gas main caused several workers at NIU Telecommunications to evacuate their office Tuesday morning.

The line was cut accidentally by independent contractors who were removing a tree located near the Department of Public Safety building, said Melanie Magara, assistant vice president of NIU Public Affairs.

“Within an hour, they had it under control,” Magara said.

Corky Wetzel, community relations director for the DeKalb County area for Nicor Inc., said a crew was in the area and responded right away. The service was repaired and has been replaced.

“I don’t know if it was marked,” Wetzel said. The area reportedly had been checked by both Nicor and Joint Utility Locating Information for Excavators Inc., better known as JULIE.

Wetzel said they are investigating the situation.

University Police Chief Don Grady said they had to rotate the telecommunication operators in the University Police in case they were feeling nauseated.

Darryl Grayson, interim superintendent of Grounds for NIU, said the independent contractors were moving a tree near the building to make way for a new air conditioning unit.

“He started putting his spade in the ground and started hearing hissing and smelled gas,” Grayson said.