Spanish Prime Minister Jose Luis Rodriguez Zapatero on Monday "firmly" condemned "the brutal terrorist attacks" in Moscow earlier in the day, DPA reported.
Spain "is especially sensitive" to the problem of terrorism, Zapatero, whose country holds the rotating European Union presidency, said in telegrams addressed to Russian President Dmitry Medvedev and Prime Minister Vladimir Putin.
Zapatero was referring to Spain's experience of decades-long violence by the militant Basque separatist group ETA, as well as to the 2004 Madrid train bombings in which Islamist extremists killed 191 people.
The Foreign Ministry also issued a communique expressing "deep sadness" as well as condolences to the victims and to the Russian people.
Dozens of people were killed Monday morning in separate blasts on Moscow's Metro train station which the Russian secret service FSB said were carried out by female suicide attackers.