They started blocking the inbound Rajvithi Road in front of the Center One shopping mall at 12:30 pm and later on blocked the inbound Phayathai Road.
The members of the Taxi Community Radio Club said if the government refused to resign by 4 pm, they would use 20,000 taxis to block all roads in Bangkok.
The red shirts led by Jakrapob Penkair have withdrawn from the Si Sao Thewes residence of chief royal adviser General Prem Tinsulanonda to Victory Monument.
More than 100 bus routes are redirected due to the shut-down of traffic at Victory Monument.
Doctors called for protesters to open at least one lane of traffic to facilitate medical services at major hospitals. Hospitals in the vicinity of Victory Monument including Rajvithi, Ramathibodi, King Mongkut, Children's General and Phaya Thai II have all been affected. Many patients are stranded and are not able to make it to these hospitals.
The red shirts later blocked the Democracy Monument on Rajdamnoen Avenue.
Police have closed off traffic around two thoroughfares at Democracy and Victory Monuments.
Traffic got worse in the evening after rain poured over most parts of Bangkok.
The Bangkok Skytrain and Subway are reportedly closed due to fears over security.
(Photo credits: The Nation)
