SAN DIEGO -- Supervisor Bill Horn Friday called for a study on the costs and impacts of illegal immigration in San Diego County.

"We are being crushed in terms of lives lost, people victimized and enormous costs by the stampede of illegal aliens," Horn said at a morning news conference outside the County Administration Building.

Horn said he will ask his colleagues on the Board of Supervisors Tuesday to authorize the county's chief administrative officer to initiate the report.

"The data we are using is terribly outdated, and because of that, there is a huge negative impact on more than 3 million people in our region who depend on county services," he said.

Information collected in the report, which will focus on "drains" to county law enforcement and social services, will be used to petition the federal government for reimbursement, according to Horn.

"The public has the right to know how much illegal immigration costs their county government, and we need the data to take appropriate action," he said.

Horn said it costs the county more than $50 million annually to provide law enforcement, criminal justice services and medical care to illegal immigrants.

The cost of providing medical treatment to illegal immigrants in the county was $119 million in 2005, according to a report provided by the supervisor from the Hospital Association of San Diego and Imperial Counties.

Joining Horn at the news conference was Republican Brian Bilbray, a former South Bay congressman who is running against Democrat Francine Busby for the 50th Congressional District seat.

Bilbray said the federal government should be "footing the bill on the services it mandates."

"On Monday, people in Washington were talking about the great benefits of illegal aliens," he said. "I say it's time the full story is told about the destructive cost that far outweighs any so-called benefit."