Earlier this week, footage surfaced online of blacked-out military helicopters flying low over downtown Los Angeles. It may seem unnerving to have special operators wearing full “battle rattle” zoom over your local grocery, but citizens of LA don’t need to fret. These low-flying birds of prey are the good guys.

The helicopters, MH-6 Little Birds and MH-60 Black Hawks, hail from the U.S. Army’s 160th Special Operations Aviation Regiment (SOAR). Its pilots are tasked with the insertion and extraction of America’s special operations troops in heavily-contested territory. They often fly extremely low with little or no external lighting, using darkness for concealment. Their tenacity for twilight operations earned them the moniker “Night Stalkers.”

In other clips, a MH-60 Black Hawk with no external lighting lands in the middle of the street, where a group of special operators exited a building and quickly climbed aboard.

The U.S. Army provided Los Angeles authorities with a forewarning of its intended training operations throughout the city. However, for many residents, that warning was perhaps not early enough. The training exercise prompted a flurry of posts on social media and calls to local law enforcement.

“Residents may hear sounds associated with the training,” the LAPD said in a news release. “Each location selected enables special operations teams and flight crews to maintain maximum readiness and proficiency, validate equipment and exercise standard safety procedures. The training is essential to ensure service members are fully trained and prepared to defend our nation overseas.”

These types of exercises aren’t uncommon. In April 2018, NEWSREP covered a group of dimly-lit helicopters from the 160th flying low over Southern Manhattan in a similar way.

Training exercises like these usually happen for one of two reasons: pre-deployment training for a specific engagement; or more generalized readiness training meant to ensure America’s special operators have the essential skills to conduct combat operations in urban environments. Drills often involve Joint Special Operations Command units infiltrating a city by other means, such as collecting intelligence or capturing targets, before the Night Stalkers spin up their rotors and head in for support or extraction.