The situation in the eastern part of Aleppo is still grim after a ceasefire to allow the evacuation of opposition fighters and tens of thousands of civilians is on the verge of collapse.

SEE ALSO: Aleppo activists post heartbreaking goodbye messages on Twitter

Shelling has resumed in the rebel part of the city and buses meant to be used in the evacuation have returned to their depots, according to Syrian activists.

It comes after trapped residents and activists took to Twitter to send heartbreaking "goodbye" messages as the Syrian government's forces closed in.

The UN's human rights office said Syrian pro-government forces have been entering homes in eastern Aleppo and killing civilians inside, including women and children.

People reacted to the reported massacre by sharing on Instagram minimalist cartoons with the Arabic name for Aleppo and blood dripping from the letters:

May God help the people of حلب the dying and the injured. So sad in this modern world to see such devastation and death .. as no one cares and all suddenly blind to see. From the Arab world to the West .. #aleppo #aleppoisburning A photo posted by Mohamedhadid (@mohamedhadid) on Dec 13, 2016 at 2:34pm PST

Halep için söyleyecek çok şey var ama şunu düşünüyorum; Rabbim sorduğunda halep için ne yaptın diye.?? Ne cevap vereceğim ne cevap vereceğiz...#halep#aleppo A photo posted by Abdurrahman Yunusoğlu (@yunusoglu83) on Dec 14, 2016 at 1:36am PST

#aleppo #aleppoisburning A photo posted by Nora {누 라 ~ (@funkanetical) on Dec 14, 2016 at 1:38am PST

Others shared variations of the cartoon, with the final letter — a 'P'— which becomes an eyelash crying blood:

#prayforaleppo #aleppo #freedom A photo posted by DI LA RA 💄 (@di1oyim) on Dec 14, 2016 at 1:30am PST

Or the famous 'Girl with a balloon' by Banksy:

Stay with #Syria. Stay with #Aleppo. A photo posted by Bir Kare Paylaş (@birkarepaylas) on Dec 14, 2016 at 1:37am PST

#حلب #aleppo #prayforaleppo 🕊 A photo posted by م💍 (@1bt1__m) on Dec 14, 2016 at 1:20am PST

Aleppo ❤👼 One world One Love #aleppo#save#the#world#sad#worldproblem#children#innocent#brokenheart#prayforthem#syria#stopkilling 💔 A photo posted by Team Love❤❤ (@chaimafivie) on Dec 14, 2016 at 1:31am PST

#aleppo #prayforaleppo A photo posted by @hzwnznlabdn on Dec 14, 2016 at 1:27am PST

The Associated Press contributed reporting.

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