Thailand's Criminal Court approved on Wednesday an extension to the detention of Mohammad Hazaei, one of the suspects in last Tuesday bombing incident in Bangkok.

Security was tightened along the route where police brought Hazaei to seek court approval for a further 12-day detention.

He was charged with conspiracy to make and possess explosive devices intended to cause harm to others.

Police investigators said they opposed bail, citing possible flight risk as the case concerned serious offences with severe punishment. In addition, the explosive devices found were especially powerful and destructive, posing a threat to the public. The suspect, if released, might tamper with witnesses or evidence.

Hazaei was taken into police custody at Bangkok main international airport last week as he was about to board a flight to Malaysia.

Three blasts occurred consecutively in downtown Bangkok on Febuary 14, injuring five people. Five Iranian suspects were charged connected to the crimes.