What should the Muslims who are prevented from fasting by the Chinese government do?

Firstly: 

We ask Allah to grant relief to our Muslim
brothers in that region, and to judge between them and their enemies on the
basis of truth, for He is the All-Knowing Judge. 

Our advice to them is to be patient and
cling steadfastly to the faith, for tests and trials are the way of Allah in
dealing with His slaves. Allah, may He be exalted, says (interpretation of
the meaning):

“Do
people think that they will be left alone because they say: ‘We believe,’
and will not be tested?

And We indeed tested those who were
before them. And Allah will certainly make (it) known (the truth of) those
who are true, and will certainly make (it) known (the falsehood of) those
who are liars, (although Allah knows all that before putting them to test)”

[al-‘Ankaboot 29:2-3]. 

Secondly: 

By the grace of Allah towards His Muslim
slaves, He has decreed that the one who is compelled will not be brought to
account for whatever he does when he is compelled, and that whatever he does
under compulsion it is all the same whether he does it or not. This includes
the fasting person who is forced to eat or drink, in the sense of real
compulsion in which he fears that he or his family may be harmed if he does
not spoil his fast. 

Shaykh Ibn ‘Uthaymeen (may Allah have
mercy on him) said: 

If he is compelled (to break his fast),
his fast is still valid and he does not have to make it up, because Allah,
may He be glorified, has waived accountability in the case of one who
disbelieves under compulsion, when his heart is at ease with faith. Allah,
may He be exalted, says (interpretation of the meaning):

“Whoever
disbelieved in Allah after his belief, except him who is forced thereto and
whose heart is at rest with Faith but such as open their hearts to
disbelief, on them is wrath from Allah, and theirs will be a great torment”

[an-Nahl 16:106]. 

If Allah has waived accountability for
disbelieving in the case of one who is compelled to do that, then it is more
likely that this is also the case with regard to lesser sins. And the
Prophet (blessings and peace of Allah be upon him) said: “Verily Allah has
pardoned my ummah for mistakes, forgetfulness and what they are compelled to
do.” 

End quote from Majaalis Shahr Ramadan
(p. 82) 

I put the question having to do with the
situation of this Chinese region to our Shaykh, ‘Abd ar-Rahmaan al-Barraak
(may Allah preserve him) and he said: 

They should refrain from eating and
drinking whenever their watchers are not present, and they may eat when they
are being watched, enough to ward off harm from themselves. And their fast
is valid and they do not have to make it up, because Allah, may He be
exalted, says (interpretation of the meaning):

“Whoever
disbelieved in Allah after his belief, except him who is forced thereto and
whose heart is at rest with Faith but such as open their hearts to
disbelief, on them is wrath from Allah, and theirs will be a great torment”

[an-Nahl 16:106] 

“So keep your duty to Allah and fear
Him as much as you can”

[al-Taghaabun 64:16].

End quote.