Rights activists have criticised the detention of a group of men in Malaysia under the controversial Internal Security Act, or ISA.
The ISA allows indefinite detention without trial.
Reports that the men had ties to an international terrorist network have yet to be confirmed.
Syed Ibrahim Syed Noh, chairman of the Abolish ISA Movement in Malaysia, told Al Jazeera that the government needs to prove the detainees' links to any security threat before making an arrest.
"There is no avenue for the use of the ISA in these cases as there is no confirmed information as to their links with any of the international terrorist organisations," Syed Noh said.
"The problem with the ISA is that it offers the provision not to disclose any information of national security value as they see fit. But how do you know that these people are allegedly terrorists?"
Scope for misuse
Syed Noh said that the scope for misuse and abuse of the ISA is very high.
"If it's a concern of national security, something which is of value to the people, then they need to be informed about these issues," he said.
"Also, when someone has been detained under the ISA, they can be coerced into confessing information that the police need to be obtain. As far as human rights are concerned, as far as principles of justice are concerned, everything must be proven first."
Hishamuddin Hussein, a Malaysian politican, has said that nine foreigners were among the detained, including four Syrians, two Nigerians, one Jordanian and a Yemeni.
Najib Tun Razak, the Malaysian prime minister, said the arrests were a pre-emptive measure in dealing with terrorism.
New Straits Times, a Malaysian newspaper, has quoted sources as saying the men were linked to Umar Farouk Abdulmutallab, a Nigerian who was charged with attempting to blow up a US-bound flight on Christmas day.
The ISA has in the past been used against suspected fighters, including members of Jemaah Islamiyah, a Southeast Asian group believed to be linked to al-Qaeda.
Malaysian authorities reportedly detained 50 people under the law last week although most of them were subsequently released, according to the advocacy movement, which said that 12 others were still in detention.
The detentions come at a time of raised religious and ethnic tensions over the use of the word "Allah" by Christians to denote their God in Malay language publications.
The government had threatened to use the ISA to keep tensions from boiling over.