If the protest by the Pitak Siam group continued into the night Saturday there was a chance for a violent incident to occur and put the protesters in danger, Gen Boonlert Kaewprasit, or Seh Ai, said in defending his decision to call off the rally.
Gen Boonlert, or Seh Ai, was speaking in an interview with a news agency on Sunday morning.
He said he had heard from news reports that the protesters who were arrested yesterday had been released.
After making the announcement to call of the rally, he immediately called Pol Gen Adul Saengsingkaew, the police chief, and Pol Lt-Col Kamronwit Thoopkrachang, the metropolitan police chief, Seh Ai said.
As for the driver of a six-wheel truck who was charged with attempted murder for ramming the vehicle into a barricade at Makhawan Rangsan bridge, hurting some police, Gen Boonlert said Pitak Siam would send lawyers to help him in his legal case.
The group would also take care of those injured and treated in hospitals.
Gen Boonlert said the police were unreasonable to use tear gas to disperse the protesters at two different spots. What happened scared away people travelling from other provinces to join the rally. Some were blocked by the authorities on their way to Bangkok.
After calling off the rally, many people called on the phone asking him why he did that so unexpectedly.
"I think I made the right decision because if the rally continued into the night there was a chance for violence to occur, such as an M79 grenade being fired into the protesters.
"I did not want to see anyone die. I am already very sad to see people injured," Gen Boonlert said.
He said the obstruction by police to prevent people from moving through Makhawan Rangsan bridge was unusual because this had earlier been agreed on by the authorities.
"The rally was a failure. We could not help the people who were obstructed to show their patriotism. From what happened, nobody would want to pursue my initiative. However, I am still of high spirit.
"I may have lost face and dignity not being able to mobilise as many people as I wanted, but I am proud there was no loss of lives," Seh Ai said.
Gen Boonlert said on Monday he woud submit a letter to resign as chairman of the foundation of old students of the Armed Forces Academies Preparatory School as he did not want to damage the organisation.