The Amtrak's Empire Builder train traveling between Seattle and Chicago derailed at around 4 p.m. local time (2200 GMT). There were about 147 passengers and 13 crew members on the train at that time, according to a statement by Amtrak.

The exact number of the injured is undisclosed, the Liberty County Sheriff's Office told local media, adding that all the other passengers have been safely evacuated.

Amtrak is a passenger railroad service company operating many passenger rail routes in the United States.

Images from the derailment scene shared on social media show train cars tipped over in a remote location surrounded by dozens of people in strong wind.

The accident happened near Joplin, a small village with only about 150 residents. Great Falls is the biggest city nearby, which is nearly 160 km away.

Local media said cell phone service in the area where the derailment occurred is very poor.

Montana Attorney General Austin Knudsen said in a statement that members of Montana Highway Patrol are assisting with rescue efforts.

A 14-member team, including investigators and specialists in railroad signals and other disciplines, would be sent to investigate the crash, the National Transportation Safety Board (NTSB) spokesman Eric Weiss was quoted by the National Public Radio as saying.

Five Amtrak cars derailed at around 3:55 p.m. (2155 GMT) Mountain Daylight Time and no other trains or equipment were involved, Weiss said, adding the train was traveling on a BNSF Railroad main track at the time.

The BNSF Railway, one of the nine North American Class I railroads, is the largest freight railroad network in North America.

On-scene images showed the accident occurred along a straight section of tracks on a sunny day. — Agencies