Three protesters were injured when Thai police fired tear gas and rubber bullets at a Bangkok rally Friday -- the third time this week -- as coronavirus cases soar and anger builds over the government's handling of the pandemic.

The kingdom is grappling with its worst virus outbreak so far and registered a new daily high of 23,418 infections on Friday.

A protester uses a slingshot against police at the rally in Bangkok
A protester uses a slingshot against police at the rally in Bangkok AFP / Lillian SUWANRUMPHA

The sluggish rollout of Thailand's vaccination programme and financial pain from restrictions is heaping political pressure on Prime Minister Prayut Chan-O-Cha's government.

Protesters gathered in Bangkok at a major intersection by Victory Monument, defying a ban on public gatherings, and set fire to sacks of rotting fruit to symbolise the economic hardship of farmers.

"These fruits can't be sold because of government failure (to manage the virus and the economy)," a female protester told a crowd of several hundred people.

A demonstrator throws a table on a fire during the protest
A demonstrator throws a table on a fire during the protest AFP / Lillian SUWANRUMPHA

Demonstrators attempted to march on Prayut's residence inside a military barracks holding a large banner that read: "Prayut must get out immediately."

Police used barbed wire and rows of shipping containers to block their path while officers fired tear gas, rubber bullets and water cannon.

Deputy National Police spokesman Kissana Phathanacharoen said protesters targetted officers with ping pong bombs, slingshots, bricks, and firecrackers.

A protester uses a tennis racket to deflect a tear gas canister
A protester uses a tennis racket to deflect a tear gas canister AFP / Lillian SUWANRUMPHA

Fourteen motorbikes were impounded, he said.

At least three protesters were injured including youth activist Thanat "Nat" Thanakitamnuay, an emergency medical centre said.

At protests on Tuesday and Wednesday in the same area, police used water cannon, tear gas and rubber bullets and some demonstrators threw firecrackers at officers.

Bangkok police, facing accusations of heavy-handedness, have insisted their approach is in line with the law and urged people not to jeopardise public health and safety.

"There is clear evidence that some people among the protest group have contracted Covid-19," Metropolitan Police Bureau chief Phukphong Phongpetra told reporters on Friday.

A young protester who blew his own hand off while throwing a firework during Wednesday's rally has tested positive for coronavirus, local media reported.

Last year a youth-led pro-democracy protest movement began in Thailand that at its peak drew tens of thousands of people to rallies demanding the resignation of Prayut, the former army chief who came to power in a 2014 coup.

But the movement lost momentum earlier this year as Covid-19 cases surged and its leaders were detained.