(KUNA) -- At least two persons were killed and 20 including 10 security personnel were wounded in a suicide explosion in northern Pakistani valley, second since morning as the election campaign ends in the country ahead of Mondays election. A suicide bomber rammed his vehicle into the media center in Mangora area of Sawat valley, police sources told KUNA. They said the explosion killed two persons and wounded 20 others including 10 security and four media personnel. The explosion badly damaged the media center that has been established for election information.