Japan and the US are continuing their latest joint anti-ballistic missile drill at the Yokosuka naval base in Japan’s Kanagawa Prefecture.

The drill began on Tuesday, and is set to wrap up on February 28th. Two battleships from Japan’s Maritime Self-Defense Force, the Kirishima and Kongo, have joined in the drills. They are both equipped with the Aegis Ballistic Missile Defense. They will be used along with the US’s latest SBX radar system.

The head of the Japan Maritime Self-Defense Force and the head of the US’s Seventh Naval fleet are acting as the drill’s co-commanding officers. Japanese media is reporting that the drill is aimed at improving missile cooperation and capabilities between Japanese and US forces. This is the fourth anti-ballistic drill held by the two countries since 2011.