In Tsunami-hit Japan, a fresh fire broke out at a reactor the Fukushima No 1 nuclear power plant early today. Smoke was bellowing out from the roof of the number-four reactor at the plant. A Tokyo Electric Power (TEPCO) spokesman said efforts are on to contain the fire. A fire and an explosion had hit the same reactor yesterday, causing a crack in the roof. Damage has also been reported to part of the container shielding the number-two reactor at Fukushima 250 kilometres northeast of Tokyo. TEPCO officials had said earlier, that the fuel rods at the number-two reactor were almost fully exposed after a cooling pump there temporarily failed.The UN atomic watchdog IAEA has said that the primary containment vessel of one of the reactors at the quake-hit Fukushima nuclear plant in Japan may have been affected by an explosion there. The International Atomic Energy Agency said that, after explosions at both units 1 and 3, the primary containment vessels of both units are reported to be intact. However, the explosion that occurred at 04:25 UTC on March 14 at the Fukushima Daiichi unit 2 may have affected the integrity of its primary containment vessel. The IAEA said, all three explosions were due to an accumulation of hydrogen gas. The IAEA said, it remains concerned over the status of the Fukushima Daiichi nuclear power plant, where sea water injections to cool the reactors in units 1, 2 and 3 are continuing. Attempts to return power to the entire Daiichi site are also continuing. The US Nuclear Regulatory Commission said, it has sent nine additional experts to Tokyo to provide assistance as requested by the Japanese government. The first members of the team left the US Monday evening and were due to arrive in Tokyo this afternoon. Meanwhile, the first tranche of relief offered by India to tsunami-hit Japan is set to reach Tokyo today. Prime Minister Manmohan Singh had announced that India will despatch 25,000 blankets to Japan as part of its initial contribution to the relief efforts in the quake-cum-tsunami hit Tohuku district. A Japanese embassy statement said in New Delhi that Prime Minister Naoto Kan has appreciated the cooperation offered by India.