TOKYO, April 7 (Kyodo) —Tokyo Electric Power Co. said Sunday up to 3 liters of radioactive water has leaked from a second underground storage tank at the crippled Fukushima Daiichi power plant.

Following the latest series of problems at the nuclear plant, the utility set up an emergency task force headed by its President Naomi Hirose.

The latest problem was confirmed after TEPCO said late Friday night that up to 120 tons of contaminated water may have leaked into the soil from one of the seven storage tanks at the complex, devastated by a series of explosions in the days after the March 2011 earthquake and tsunami.

Around 10,400 tons of radioactive water, cleansed of cesium, remains in the second tank, TEPCO said.

The tank is adjacent to the one where the initial leak was reported, according to TEPCO.

The seven tanks, which are of the same design and covered by three layers of waterproof sheeting, were set up to store water used to cool the plant's nuclear reactors.

The utility examined water that accumulated on the sheeting around the second tank Saturday and detected highly concentrated radioactive substances.

Since the announcement on Friday, TEPCO has been transferring tons of the remaining water to other underground storage tanks at the site.

The transfer is expected to be completed Thursday, two days after the company's initial plan.

On Saturday, TEPCO said it believes radioactive water is unlikely to flow into the sea from the first leaking storage tank located 800 meters from the shoreline.

It said the water would soak into the soil as there is no drain around the site to the sea.