A reactor at Japan’s Oi nuclear power plant restarted over the weekend amid what have been described as the largest protests seen in the country in half a decade, according to reports.

It is the first reactor to come back online after a countrywide closure of plants in the wake of the devastating tsunami and Fukushima nuclear disaster. A second reactor is set to be restarted later this month, since Prime Minister Yoshihiko Noda gave the go ahead in June.

Hundreds of protestors are said to have gathered at a town nearby the reactor, while thousands reportedly took to the streets of Tokyo on Friday, carrying placards with the face of the Prime Minister and the phrase “Noda Yamero!” – or “Noda, stop!”

The country is said to have put in place a number of electricity savings targets today in a bid to avoid power outages over the summer.