National police chief Pol Gen Chakthip Chaijinda on Thursday insisted police officers had no choice but to enforce the law and arrest youth protest leaders this week.
Pol Gen Chakthip said police officers are bound by duty to make the arrests because the protest leaders broke the law.
Failure to act against the leaders would result in police being charged with dereliction of duty under Section 157 of the Criminal Code, he said, adding he's instructed officers to maintain neutrality and avoid taking sides between two youth protest groups.
Pol Gen Chakthip made the statement after he was asked about the arrests yesterday by a House committee vetting the budget bill for next year.
The Criminal Court yesterday approved bail requests for nine of the protesters, including human rights lawyer Arnon Nampa and two rappers. They were arrested yesterday and Wednesday for their roles in the July 18 and Aug 3 rallies.
Before their requests were approved, the court ordered them not to repeat the same offences.
The court also allowed politicians and educators to act as guarantors, including three Move Forward Party MPs, two Pheu Thai Party MPs and four academics.
Five more people, including two more rappers, were arrested on Thursday.
Not everyone arrested on Thursday received summonses; two are held on court-approved arrest warrants.
They are Dechathorn "Hockhacker" Bamrungmuang, a founder of well-known hip-hop group Rap Against Dictatorship; activists Tossaporn Sinsomboon, Tanee Sasom, and Nattawut Somboonsap; and Thanayut "Book" Na Ayudhya, a rapper from Eleven Fingers band.
They acknowledged charges and were being sent to the Criminal Court as police sought to detain them.
Their charges are believed to be similar to those faced by three people held earlier, which range from sedition to violation of the cleanliness law.
Pheu Thai MPs Karun Hosakul said he and his fellow MPs have prepared salary certification letters to be used as surety for their temporary release, as they are acting as guarantors.
On Wednesday evening, four people were arrested, including Mr Arnon, who was the first to be held in this round of arrests.
Mr Arnon, who was released on bail on multiple charges, including sedition in connection with the July 18 rally, faces more charges related to the Aug 3 rally, when he talked about the need for reforms to the monarchy.
Police charged the four with violating Section 116 of the Criminal Code; Sections 4, 10 and 15 of the Public Assembly Act, using loudspeakers without prior approval and violating the Computer Crime Law.
The officers had opposed bail for the human rights lawyer, citing Mr Arnon's alleged tendency to incite rallies.
The court granted Mr Arnon bail on Thursday.
According to the police's court request for his detention, Mr Arnon's speech given on Aug 3 criticised the monarchy and caused hatred among demonstrators.
Those others arrested on Wednesday night were Suwanna Tanlek, 48, a labour activist who has campaigned for workers' rights; Baramee Chairat, 53, secretary-general of the Assembly of the Poor; and activist Korakot Saenyenphan, 27.
They were arrested separately in Bangkok on charges of inciting public unrest and other offences related to the July 18 Free Youth rally.
Pol Col Kissana Phathanacharoen, deputy spokesman for the Royal Thai Police, said police have issued arrest warrants for 21 Free Youth demonstrators who broke the law during their three anti-government rallies.
"If we don't follow the law, how can we live?" Deputy Prime Minister Prawit Wongsuwon said.