A helicopter crashed in Washington state Wednesday night near a military base, the Army said.
The Army said in a statement that the crash happened in a rural area near Joint Base Lewis-McChord at approximately 9 p.m. local time Wednesday.
"This remains a developing situation, and no additional details are available currently," the Army said Thursday.
It wasn't immediately clear how many people were on board the helicopter or what their condition was.
Thurston County Sheriff Derek Sanders said in a Facebook post that the crash was near Summit Lake, west of the state capital of Olympia.
At one point, deputies were unable to continue rescue efforts because "the scene is on fire and is starting to overheat their footwear," Sanders said.

Eleanor Watson contributed to this report.
Brian Dakss is a longtime New York-based editor and writer for CBS News, at the Radio network and with CBSNews.com. He has written and edited for NBC News, Dow Jones and numerous radio stations and been a radio anchor and reporter.