"I've got friends who have run out of food, their communities don't help them as they are foreigners, no information to let us know what's going on and it seems more and more panic seems to be causing breakouts of fights between the locals as everyone is starving.

"It's really tough for us right now. I don't know how the locals have lasted so far in such strict lockdown measures.

"If this was anywhere in Europe, by day five of not having food people would be rioting on the streets."

'I'm very afraid'

Lockdown has had severe impact on the city's medical services.

Liang Liang, a woman from Sichuan province in southwest China, took her 66-year-old mother to Shanghai for surgery to treat her cancer, originally scheduled for last month.

But her mother tested positive for COVID on a rapid antigen test and now can't enter the hospital until she receives a negative PCR test.

"My mother's whole body feels painful," she told Sky News.

"She has a fever and is sweating. She is very weak now.

"So I'm very afraid that if we leave the hotel to go to the hospital and my mother's test result is positive, we would have to sleep on the street as we cannot enter the hospital."

Lang Xianping, a well-known economist, said on social media that his 98-year old mother died from a kidney disease after waiting four hours outside the hospital, while her test result was being processed.

"I hope this sort of tragedy won't happen again and I thank people for all their concern," Mr Lang wrote.

Makeshift hospitals with huge capacity

The city has built more than 100 makeshift hospitals, with capacity for 160,000 patients.

Anyone who tests positive for COVID-19 must be sent to one of those hospitals, rather than isolate at home. Conditions in the hospitals vary massively.

Jane Polubotko, a Ukrainian expat in Shanghai, was sent to one of those centres two weeks ago after testing positive

Four thousand people are living there in a vast exhibition hall, with beds in cubicles next to each other, basic toilets and no shower.

'People get desperate'

"The lights are never off," she told Sky News.

"I really cannot comprehend it and I do not understand the reason behind it. The longer we stay here, it gets more difficult to be here.

"The level of anxiety is quite is quite high and not only for me, but for the people around here. Everyone is very nervous and frustrated and anxious.

"People have started arguing with the medical staff on the regular basis - very, very often.

"And right now, it's 24/7 that people are arguing with the staff. There's a lot of different problems."

Ms Polubotko has tested negative twice in a row for COVID 19, the requirement for being discharged, but still has not been told whether she can leave.

"People just get desperate because you don't really know how to get out of here."