Spain has ramped up its security plans ahead of the Champions League quarter-finals matches in Madrid this week due to a potential threat of terrorism.
"To prevent any terrorist threat, the state security forces have activated all of their early warning and protection systems as well as their defence mechanisms," the Spanish Ministry of the Interior said.
On Tuesday, Real Madrid host Manchester City, while Atletico Madrid welcome Borussia Dortmund on Wednesday.
The ministry didn't explicitly mention possible terrorism threats from Islamist groups, but the Spanish media spoke of possible threats from jihadists.
The the federal and state security forces have taken all necessary measures to ensure the safety of participants and visitors in the two games as well as Spanish citizens in general, the ministry further emphasized.
Some 2,000 police officers and other security personnel are to ensure that the two games go ahead safely.