(Reuters) – An advanced U.S. military anti-missile system was used in Israel to try to intercept a projectile for the first time since President Joe Biden placed the system in Israel in October, a source familiar with the matter told Reuters on Friday.

The THAAD, or Terminal High Altitude Area Defense system, was used to try to intercept a projectile from Yemen sometime during the last 24 hours, and an analysis would determine its success, said the source who spoke on condition of anonymity.

The Pentagon did not immediately respond to a request for comment.

Israel struck multiple targets linked to the Iran-aligned Houthi movement in Yemen on Thursday, including Sanaa International Airport, and Houthi media said at least six people were killed.

Houthis have repeatedly fired drones and missiles towards Israel in what they describe as acts of solidarity with Palestinians in the Gaza Strip.

In October, Biden placed the THAAD system, built by Lockheed Martin (NYSE:), in Israel along with about 100 U.S. soldiers to help defend the country.

THAAD is a critical part of the U.S. military’s layered air defense systems and added to Israel’s already formidable anti-missile defenses.