Demonstrators gather for a rally in Hong Kong.

Hong Kongers are set to rally over concerns about police conduct in monthslong pro-democracy demonstrations, including exposing police dogs to tear gas during chaotic confrontations with protesters.

Organisers plan a demonstration at a waterfront park on Sunday afternoon.

Hong Kong police have faced criticism for heavy-headed tactics including tear gas, pepper spray, rubber bullets and a water cannon to subdue protesters who have hurled bricks and firebombs.

Police dogs were seen at protest clearance operations without any protective gear while riot officers wearing respirator masks fired tear gas.

The movement's supporters say exposing dogs to tear gas amounts to animal cruelty and threatens their lives.

The force says on its Facebook page that "no police dog has passed away or felt unwell as a result of handling protests since June."

Associated Press