MOSCOW – A 17-year-old from Dagestan was one of two female suicide bombers who attacked Moscow's subway, Russian investigators said on Friday. A leading newspaper called her the widow of a slain Islamist rebel. President Dmitry Medvedev also urged harsher measures Friday to crack down on terrorism and the death toll from Monday's subway bombings rose to 40 as a man died in the hospital. At least 90 others were injured in the twin subway attacks. Federal investigators identified one of the attackers as Dzhanet Abdurakhmanova, 17, of Dagestan and said they were still trying to identify the second bomber and track down the organizers of the attack. Dagestan, one of the predominantly Muslim provinces in Russia's volatile North Caucasus region, was the site of two suicide bombings on Wednesday that killed 12 people, mostly police officers. Another explosion there Thursday killed two suspected militants. The Kommersant newspaper published what it said was a picture of Abdurakhmanova, also known as Abdullayeva, dressed in a black Muslim headscarf and holding a pistol. A man with his arm around her, also holding a gun, is identified as Umalat Magomedov, whom the paper described as an Islamist militant leader killed by government forces in December. The paper said the second subway bomber has been has been tentatively identified as 20-year-old Markha Ustarkhanova from Chechnya, the widow of a militant leader killed last October while he was preparing to assassinate Chechen President Ramzan Kadyrov, who is backed by the Kremlin.