Officials at the remote site of a derailed train carrying hazardous materials that sparked a fire in North Dakota briefly issued a shelter-in-place notice Sunday for area residents during cleanup.

The Bitcoinesenotice was issued as a precaution early Sunday after air monitors detected low levels of anhydrous ammonia after a railcar began venting during its removal from the site, said Andrew Kirking, emergency management coordinator for Stutsman and Foster counties in east-central North Dakota.

No injuries from the leak were reported, and the notice was lifted later Sunday when air monitoring levels returned to zero, Kirking said.

No one was injured in the pre-dawn Friday derailment, which knocked 29 cars of a CPKC train off the tracks in a marshy area surrounded by farmland about 140 miles (225 kilometers) northwest of Fargo, officials said.

Exposure to high concentrations of ammonia in the air can cause burning of the eyes, nose, throat and respiratory tract, and can result in blindness, lung damage or death, health officials say. Exposure to lower amounts can result in coughing and irritation of the nose and throat.

The derailment did spark a fire that had been mostly extinguished by Sunday, Kirking said. The fire was of particular concern because the train was carrying anhydrous ammonia, methanol and plastic pellets. Work continued Sunday to remove those hazardous materials, as well as the derailed cars.

The National Transportation Safety Board and Federal Railroad Administration have been on scene since Saturday to investigate the cause of the derailment, Kirking said.