At least one of them had already been deported back to Pakistan by Friday morning and another three deportation orders were pending, their lawyer said.
"They are genuine students. They (authorities) are ruining the future of these kids," lawyer Sotiris Drakos said.
Cypriot Interior Minister Andreas Christou declined to give more details or say why deportations would be an option for individuals considered a security risk.
"I can confirm that instructions were given for their arrest for security reasons, nothing more," he said.
The Pakistanis were arrested in a police swoop in the holiday coastal town of Larnaca on Wednesday. Their lawyer said the arrest warrant he had seen made no reference to security.
Asked about the arrests, a police spokesman said: "Matters which relate to state security and terrorism are not issues we comment on."
"They are genuine students. They (authorities) are ruining the future of these kids"
Western governments consider "terrorism" threat as low on Cyprus, perched on the edge of the Middle East.
The island is a melting pot of cultures and attracts hundreds of thousands of visitors every year to its lively tourist resorts.
Cyprus also houses two British military bases on its south coast dating from British colonial rule that ended in 1960.
The Pakistanis are being held at four different detention centres. Under Cypriot law, there is no need for a public court appearance if deportation orders are issued.
"We have seen nothing on the one arrest warrant we saw relating to security," Drakos said. "It said their resident permits had run out."