KEELUNG, Taiwan (AP) — China says it has conducted “precision missile strikes” in the Taiwan Strait as part of military exercises by its navy, air force and other departments in six zones surrounding the island. The drills were prompted by a visit to the island by U.S. House Speaker Nancy Pelosi this week. They are intended to advertise China’s threat to attack the self-governing island republic in response to moves to solidify its de facto independence from Chinese rule. China’s official Xinhua News Agency said the exercises were joint operations focused on “blockade, sea target assault, strike on ground targets, and airspace control.” Taiwan has put its military on alert and staged civil defense drills, while the U.S. has numerous naval assets in the area.