GAZA, Feb 14 (Reuters) - The Gaza Strip's only power station, which supplies the Palestinian enclave with up to two-thirds of its energy needs, was shut down on Tuesday because of a shortage of fuel smuggled in from neighbouring Egypt.

The closure led to widespread blackouts for Gaza's 1.7 million inhabitants. The local power company warned that households would receive only six hours of electricity a day until the problem was resolved.

Gaza's Energy Authority, which is run by the Islamist Hamas group, said "measures taken" on the Egyptian side of the border meant not enough fuel was entering the territory.

It did not provide further details. Some local experts said Hamas had mismanaged Gaza's power needs by failing to provide a viable alternative to the precarious smuggling routes.

The Gaza power plant needs 600,000 litres of fuel a day to keep running, but the Palestinian Centre for Human Rights (PCHR) said only 340,000 litres had arrived from Egypt since Friday, with no reserve stocks left in Gaza to cover the shortfall.

"We are sorry to announce that we are unable to provide hospitals, education premises, water pumps and waste water facilities and all other fields of life with the enough quantities of electricity," said Abu Al-Amrain, information director at the Energy Authority.

He urged Egypt to allow more fuel into Gaza, but did not explain what had caused the sudden drop in the flows.

Locals said in normal circumstances a fleet of trucks arrived at the Egyptian side of the border and pumped fuel through pipes in the smuggling tunnel that led into Gaza.

Israel provides the Mediterranean territory with at least 35 percent of its energy needs, but closed off its own fuel pipeline into the enclave in January 2010.

Abu Al-Amrain said Israel bore overall responsibility for the ongoing crisis, but Mustafa Ibrahim, a human rights researcher and writer, said Hamas's administration had failed to provide the territory with an energy safety net.

"(The Energy Authority) made everything depend on fuel smuggled through the tunnels, without having any guarantees that this flow could continue. The current severe crisis is evidence that this was the wrong approach," he said.

The sound of generators roared in Gazan streets as businesses tried to keep the lights on, but the PCHR warned that the power cuts could have serious consequences.

"The current crisis may impact access ... to vital services, including the supply of drinking water," it said in a statement.

Gaza's precarious energy supply is bad at the best of times, with a rickety infrastructure system badly degraded during fighting between Israel and Hamas over the past five years.

Israel maintains a blockade by land, air and sea on Gaza to prevent weapons and material with potential military use from reaching Hamas, which is committed to destroying the Jewish state.