After the contested election, President Bush sent in US forces to overthrow Noriega on the grounds that hostile acts were performed against US military personnel. Noriega declared a state of war and the US launched an attack called "Operation Just Cause" with 24,000 troops. The fighting lasted several days and Noriega hid at the Papal Nunciature office during this time. Finally, after pressure from Vatican officials Noriega surrendered in January 1990.