MINNEAPOLIS — Horse owners in the Twin Cities area are being urging to quarantine the animals due to a deadly equine virus, even though they may not be showing symptoms of the illness.

University of Minnesota specialist Christie Ward says seven horses have shown signs of neurological defects, including four that have tested positive for the virus. Three horses have been euthanized. One is recovering. Test results are pending on the others.

Officials say the outbreak is in a region around the Twin Cities, including Chisago, Dakota, Hennepin and Winona counties and western Wisconsin.

Ward said the majority of horses diagnosed had been barrel-racing and were in close contact with other horses. Officials are recommending a quarantine.