MAKHACHKALA, Russia — A team of U.S. investigators is speaking with the parents of the two Boston bombing suspects in southern Russia.

The official said Wednesday that the team is working with the Russian security services, the FSB.

The mother of Tamerlan and Dzhokhat Tsarnaev is being interviewed today in the FSB building in Makhachkala, the capital of Dagestan.

BEIJING — A new strain of bird flu that emerged in China over the past month is one of the “most lethal” flu viruses so far, worrying health officials because it can jump more easily from birds to humans than the one that started killing people a decade ago, World Health Organization officials said Wednesday.Scientists are watching the virus closely to see if it could spark a global pandemic but say there is little evidence so far that it can spread easily from human to human.Health experts are concerned about H7N9's ability to jump to humans, and about the strain's capacity to infect birds without causing noticeable symptoms, which makes it difficult to monitor its spread.