Police have been deployed in front of the 11th Infantry Regiment headquarters in Bang Khen district on Phahon Yothin road ahead of the demonstration by anti-government protesters.
The demonstration was scheduled to start at 3pm.
Rolls of barbed wire were laid in front of the 11th Infantry Regiment headquarters, blocking the entrance and exit gates. Black plastic sheets were used to cover the unit's name sign to prevent it from being vandalised with coloured paint.
The wrecks of two old buses were also placed to block the entrance and the exit.
Pol Col Krisna Pattanacharoen, deputy spokesman of the Royal Police Office, asked people to monitor official announcements about traffic conditions and roads to avoid.
The police would maintain law and order outside the compound, while the inside would be safeguarded by army soldiers, he said.
Parit "Penguin" Chiwarak, a protest leader, reportedly arrived at Wat Phra Sri Mahathat temple ahead of the scheduled protest time.
