mark shields, ramesh ponnuru, thank you. >> thank you. you're welcome.tinue our series, "china: power and prosperity," with what the u.s. calls "one of the worst human rights crises of our time." ghurs are muslims who trace their roots through thousands of years to central asia. today, most of them, about 11 million, live in the chinese province xinjiang. they represent less than 1% ofer the populati in a country that 9 is more th han chinese, the ethnicity that china traces back to an ancient empire. e communist china has long persecuted people based on their religion.te but the u.s., ational groups, and uighurs say this is different. inthey accuse china of thr uighurs into camps, and targeting their religion and entire culre. with the support of the pulitzer center, nick schifrin reports avfrom a city many uighurs fled to-- istanbul. >> schifrin: istbul is 2,500 miles from xinjiang, china. muslim uighurs who live here are free, but their minds are still imprisoned. >> ( translated ): i never imagined this could happen in the 21st century: innocent peop

mark shieldsnd ramesh ponnuru are here to analyze the swirling impeachment investation, and

mark shields and ramesh ponnuru the widening investigation into president trump., much more. >> woodruff: returning now to our main story, the eastern country of ukraine lies at ntthe heart of the impeach inquiry. we've sent special correspondent simon ostrovsky there, to reporr on what' and what's not in the story of hunter and joe biden. >> reporter: how did ukraine find itself suddenly in the middle of an american impeachment investigatatn? the heart of e matter are ev16ts that took place in 20 when former vice president joe biden threatened to pull a biion dollars in loan guarantees from the struggling post-soviet nation, if itsal prosecutor genasn't fired,t fi echoing the demands of other allies and the international monetary fund, who wanted ukraine's judicial system rid of corruption. but, president donald trump alleges that biden did this in neder to stop anestigation into a ukrainiany company called burisma, which his son hunter served on the board of. >> somebody ought to look into joe biden's statement, because it was disgraceful. >> reporter: it all ce