LOS ANGELES (Reuters) – Federal agents in California arrested 280 foreigners with criminal records, most for serious offenses, in their largest such crackdown to date, U.S. immigration officials said on Friday.

More than 100 of those rounded up in a three-day sweep that ended late Thursday have since been expelled from the United States, and most of the rest face immediate deportation proceedings.
The bulk of the individuals had prior convictions for crimes such as rape and armed robbery and assault with a deadly weapon.
“These are not people we want walking our streets,” Assistant Homeland Security Secretary John Morton said at a news conference in Los Angeles.
He touted the statewide sweep as the biggest such operation by the U.S. Immigration and Customs Enforcement (ICE) agency.
But the latest arrests represent a fraction of the 136,000 individuals expelled during the past year under stepped-up U.S. efforts to find and remove serious criminal offenders who are fugitives from deportation.
ICE estimates that 560,000 “fugitive aliens” -- a mix of people wanted for deportation who have criminal records and some who do not -- are still at large in this country.
Officials could not say how many such fugitives remained in the country after serving time in U.S. prisons. But a breakdown of cases tallied in this week's sweep suggests the numbers are high.
The lion's share, 217, had managed to avoid expulsion after their incarceration, ICE spokeswoman Virginia Kice said.
Some escaped detection because they served time in state and local jails before “we had the programs to identify those cases and ensure follow-up enforcement action,” Kice said.
Others were free from custody during their prior deportation proceedings and slipped away. she said.
Over 60 of those arrested this week were previously deported but snuck back into the United States. At least 17 of those face further federal prosecution for reentering the country illegally, an offense punishable by up to 20 years in prison, ICE officials said.
Most of those arrested this week are from Mexico or Central America, but 30 different nations in all were represented, including countries in Europe, the Middle East and Africa.