UPDATE 1-US immigration raids violated constitution - suit

(Adds immigration agency comment)

By Jon Hurdle

PHILADELPHIA, April 3 (Reuters) - U.S. immigration officers violated the rights of suspected illegal aliens by forcing their way into homes in pre-dawn raids, a lawsuit filed on Thursday says.

The officers woke suspects in eight New Jersey homes by pounding on doors between August 2006 and January 2008.

They ordered children out of beds, shouted obscenities and shoved guns into people's chests, according to the suit filed in federal court in Newark, New Jersey, by Seton Hall Law School's Center for Social Justice and the law firm Lowenstein Sandler.

An Immigration and Customs Enforcement (ICE) spokeswoman said she could not comment on pending litigation but that "ICE agents conduct themselves professionally."

The suit links the raids with "Operation Return to Sender," the immigration agency's campaign to arrest more immigrants, focusing on criminals. Operation Return to Sender ended on June 13, 2006, but immigrants' rights campaigners say its practices continue.

The agency said it arrested 2,179 illegal aliens during the three-week sweep, about half of whom had criminal records. There are an estimated 12 million foreign nationals living illegally in the United States.

"Our complaint shows that what happened to our plaintiffs in the middle of the night ... was part of a routine, widespread practice, condoned at the highest levels," Seton Hall attorney Bassina Farbenblum said in a statement.