The Afghan government took official control of the southern Taliban stronghold of Marjah Thursday, installing an administrator and raising the national flag while US-led troops worked to root out final pockets of militants. The ceremony was held in a central market as US Marines and Afghan troops slogged through bomb-laden fields in the north of the town. The Marines and their Afghan partners are trying to secure a 28-square mile area believed to be the last significant pocket of insurgents in Marjah. Militants and allied troops are still getting caught up in gunfights in some areas, NATO said. But the number of residents returning has increased in recent days, shops have opened to sell telephones and computers alongside fresh fruits and vegetables, and officials hailed the installation of Abdul Zahir Aryan as the town's administrator as a key sign of progress. Some 700 residents gathered to see Aryan formally appointed as the top government official in Marjah, along with government officials and Brig. Gen. Larry Nicholson, commander of US Marines in Marjah, said officials at the event.