Amnesty International on Wednesday accused Spanish authorities of using racial and ethnic profiling, with police singling out people who are not white in order to meet quotas.

In a new report, the human rights group said some police stations in Madrid have weekly and monthly quotas for ID checks and detentions of immigrants not carrying residency papers or work permits, encouraging officers to target people belonging to ethnic minorities, even if they are living legally in Spain as residents or are citizens.

"People who do not 'look Spanish' can be stopped by police as often as four times a day," said Izza Leghtas, the Amnesty researcher who investigated and wrote the Spain report.

The group said African and Latin American immigrants _ both legal and illegal _ are most frequently targeted by officers who demand their IDs in neighborhoods with heavy immigrant populations, on public transportation and in parks.

A spokeswoman for the Interior Ministry on Wednesday said the ministry rejects the allegations and does not carry out racial profiling. She was not aware if ministry officials had received a copy of the Amnesty report.

She spoke on condition of anonymity because of department policy.

Amnesty said that under Spanish law police can check the identity of people in public places when there is a security concern. The group's research, however, revealed that deliberate identity checks on foreigners without any security concern is widespread.

"It is not only discriminatory and illegal _ it also fuels prejudice _ as those who witness such stops presume the victims to be engaged in criminal activities," said Leghtas.

Spain has more than 5 million foreign nationals, making up some 12 percent of the population. About half are European Union citizens while Moroccans, Ecuadoreans and Colombians form the largest groups of non-EU nationals.

Legal immigrants are often caught up in the sweeps, Amnesty said.

"Looking like a South American isn't a crime," said Miguel Angel Calderon, the group's Spain spokesman. "They have the right to go out and buy bread and take their children to school without being scared they'll be stopped."

Spain underwent a wave of immigration from the 1990s to 2008 amid an extended economic boom that was cut short in 2008 by the financial crisis and a recession that lasted nearly two years. Leghtas said successive Spanish governments have used "stop and search powers abusively as a way to control migration."

Spain now has a euro-zone high unemployment rate of 21.5 percent. The unemployment rate among foreign nationals is 32.6 percent. Amnesty said it has anecdotal evidence the ID checks targeting nonwhites also happen elsewhere in Spain, but that its study focused only on Madrid.