quantities of steam and oxygen. The pressure produced by the expanding HTP ruptured the kerosene fuel tank in the torpedo and set off an explosion equal to of TNT. The submarine sank in relatively shallow water, bottoming at about off Severomorsk, at . A second explosion 135 seconds after the initial event was equivalent to 3-7 tons of TNT. The explosions blew a large hole in the hull and caused the first three compartments of the submarine to collapse, killing or incapacitating all but 23 of the 118 personnel on board. Rescue attempts The British and Norwegian navies offered assistance, but Russia initially refused all help. All 118 sailors and officers aboard Kursk died. The Russian Admiralty initially told the public that the majority of the crew died within minutes of the explosion, but on 21 August, Norwegian and Russian divers found 24 bodies in the ninth compartment, the turbine room at the stern of the boat. Captain-lieutenant Dmitri Kolesnikov wrote a note listing the names of 23 sailors who were alive in the compartment after the boat sank.Kursk carried a potassium superoxide cartridge of a chemical oxygen generator; these are used to absorb carbon dioxide and chemically release oxygen during an emergency. However, the cartridge became contaminated with sea water and the resulting chemical reaction caused a flash fire which consumed the available oxygen. The investigation showed that some men temporarily survived the fire by plunging under water, as fire marks on the bulkheads indicated the water was at waist level at the time. Ultimately, the remaining crew burned to death or suffocated. Russian President Vladimir Putin, though immediately informed of the tragedy, was told by the navy that they had the situation under control and that rescue was imminent. He waited for five days before ending his holiday at a presidential resort in Sochi on the Black Sea. Putin was only four months into his tenure as president, and the public and media were extremely critical of his decision to remain at a seaside resort. His highly favourable ratings dropped dramatically. The president's response appeared callous and the government's actions looked incompetent. A year later he said, "I probably should have returned to Moscow, but nothing would have changed. I had the same level of communication both in Sochi and in Moscow, but from a PR point of view I could have demonstrated some special eagerness to return."