Maj Gen Wara Boonyasit, commander of the 1st Division, King's Guard, announced the plan on Wednesday during a meeting with senior military officers.
The meeting was called to discuss adjusting security measures after unidentified gunmen carried out a series of late-night gun and grenade attacks on People's Democratic Reform Committee (PDRC) protest sites in Lumpini, Ratchaprasong and Pathumwan on Monday and Tuesday.
The gunmen also exchanged gunfire with soldiers deployed to provide security around PDRC rallies.
The extra 117 military security and surveillance checkpoints, in addition to the existing 29, will be set up around every rally site, parts of the city deemed vulnerable to violent attacks and crowded areas, Maj Gen Wara said.
He said soldiers will perform their duties to provide safety for all sides — the authorities, the general public and the protesters.
Routes for military patrols would be adjusted to suit each area and the frequency of patrols would be increased in an attempt to prevent and suppress violence as much as possible, he added.