What in the world does the AP mean by “reliable?”

The Iranian state news agency reported Wednesday that the country’s former nuclear negotiator, Hossein Mousavian, has been arrested on an unspecified security charge. Citing an “unofficial informed source,” the reliable IRNA agency said Mousavian was arrested in Tehran on Monday. He was a member of the Iranian nuclear negotiator team until 2005, and also served as Iran’s ambassador to Germany in late 1990s and early 2000s.

Like, they always file their dispatches on time or they are honest in their reporting? I hope the AP means the first…