General David Petraeus, the commander of US forces in the Middle East and Central Asia, arrived here in Pakistani capital today (Wednesday) on a surprise visit, report said. Soon after his arrival in Islamabad, Petraeus visited the General Headquarters (GHQ) in Rawalpindi where he met with Chief of Army Staff General Ashfaq Pervez Kayani. The two military officials discusses war on terror, the security situation of Pak-Afghan border area and ways to enhance defence cooperation between Pakistan and US.