Bogota, Aug 8: Elected President on promises to battle endemic corruption and negotiate peace with a 34-year-old Leftist insurgency, Andres Pastrana was sworn in on Friday facing massive challenges.Colombians hope the 44-year-old former television journalist can restore authority to an office whose clout was eroded under the scandal-plagued administration of outgoing President Ernesto Samper.Thursday's inauguration of the Conservative Party leader and former Bogota mayor took place in the capital's Central Plaza and was attended by about 5,000 people, including visiting dignitaries and eight heads of state.Pastrana took the oath of office and received the presidential sash on a platform trimmed with white, pink and red roses in front of the colonial Congress building. A military band stood at attention and Colombian flags flapped in the breeze. Prince Felipe of Spain also attended the ceremony.Before the ceremony, Pastrana prayed at the grave of his late father, former president Misael Pastrana,at nearby San Ignacio church.Congress cleared the outgoing President Samper in 1996 of charges of knowingly accepting $6 million in campaign contributions from cocaine lords in his campaign against Pastrana four years ago. But under Samper, the president's authority suffered, Colombia's economy declined and the rebel movement grew.