VIENNA, Dec. 26 (UPI) -- Police in Vienna have notified several European cities of a possible terror threat expected between Christmas and New Year's Eve.
The authorities were tipped off by an anonymous but "friendly" intelligence service warning some capitols in the region may be the focus of attacks involving guns and explosives, The Guardian reports. No special events in Vienna will be canceled amid the threats, but surveillance is expected to be heightened.
The anonymous tip was reportedly sent to the Vienna police in the days prior to Christmas and included a list of names of possible offenders. However, specific locations affected by the reported threat have not been disclosed.
"We do not know if these people exist in real life, or if they are only names with no real person behind them," Vienna police spokesman Christoph Polzl told the Guardian. "We have no evidence that they are in Vienna, and we have no evidence that they are even in Europe."
European police forces are reportedly on high alert in response to the threats while Vienna police promise thorough security checks of people and unaccompanied suitcases and bags, CNN reports.
The threats come several weeks after attacks in Paris left 130 people dead.