Why were the Iraqi detainees made to pick up garbage?

Germany—The commander of three British servicemen accused of mistreating Iraqi detainees testified Friday that he told soldiers to make their prisoners "work hard" picking up garbage but saw no abuse. A Danish army captain and four military police sergeants, meanwhile, were formally charged with mistreating Iraqi detainees at a military camp near Basra last year.
Question: Why were the Iraqi detainees made to pick up garbage?

A gunman has killed at least 30 people at a university in the American State of Virginia. The shooting was the deadliest ever in American history. The gunman was also killed. The police chief at Virginia Tech in Blacksburg said several people were wounded.
Question: Where did the shooting take place?