A day after a Pakistani man was sentenced to 30 years in prison for an unsuccessful plot to bomb a busy subway station, federal immigration authorities detained his parents and sister with the intent to deport them, a newspaper said Wednesday.

Shahwar Matin Siraj, 24, was sentenced Monday in Brooklyn federal court for a 2004 plot to blow up the Herald Square subway station in a congested shopping district where Macy's has long had its flagship store.

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A spokesman for Immigration and Customs Enforcement told the New York Times that Siraj's father, Siraj Abdul Rehman, 54, was arrested after a final deportation order was filed against him. Siraj's mother, Shahina Parveen, 50, and his sister, Sanya Siraj, 19, were arrested and detained on other immigration violations, the newspaper said.

The family has lived in the United States since 1999 and had been seeking asylum since 2003.

Siraj was convicted of conspiracy last year in a case that authorities hailed as a victory against homegrown terror. But Siraj claimed he was entrapped by a police informant, who inflamed him to hatch the failed subway bomb plot by showing him pictures of abuse of Iraqis. There was no proof that the plot went beyond the planning stages or that Siraj had connections to terrorist organizations.

Mark Thorn, a spokesman for the immigration agency that detained Siraj's family members, said he could not say why the actions were taken a day after the man was sentenced, the newspaper reported, but said only that criminal cases take precedence over administrative ones.

Mona Shah, the family's lawyer, told the New York Times that she knew of no final order of removal entered against Rehman.

"It's absolutely disgusting that they've picked him up under the guise of a deportation order," Shah told the Times. "Fine, punish the son. But why punish them like this?"

All three of Siraj's family members were picked up Tuesday morning at their home in Queens and are being held at a facility in Elizabeth, N.J.