17.06: The Tokyo Electric Power Company has said the pressure inside the No. 1 reactor at its Fukushima-Daiichi nuclear plant has been rising, with the risk of a radiation leak, according to the Jiji Press news agency. Tepco planned to take measures to release the pressure, the report added. The reactor's cooling system began to malfunction after the earthquake. People living close to the plant were later evacuated as a precaution. 1708: Nuclear physicist Dr Walt Patterson tells the BBC it sounds like there is a "serious problem" at the Fukushima-Daiichi plant. "It's the sort of thing that nuclear engineers have nightmares about," he says. "If it is not resolved in the next few hours it will get serious. If the core is uncovered, then those rods at the top may get hot enough to melt themselves."