MOSCOW

- Two suicide bombings in as many days have killed 31 people and raised concerns that Islamic militants have begun a terrorist campaign in Russia that could stretch into the Sochi Olympics in February. Russian and international Olympic officials insisted the site of the games, protected by layers of security, is completely safe.

The attacks in Volgograd, about 400 miles from Sochi, reflected the Kremlin's inability to uproot Islamist insurgents in the Caucasus who have vowed to derail the games, the pet project of President Vladimir Putin.

No one has claimed responsibility for Sunday's blast at the Volgograd railway station or yesterday's bus explosion in the city, but they came only months after Chechen rebel leader Doku Umarov threatened new attacks on civilian targets in Russia, including the Olympics.

In addition to the dead, the bombings wounded 104 people, according to Russia's Health Ministry. Late yesterday, 58 remained hospitalized, many in grave condition.

Electricity usage down in U.S. homes

NEW YORK

- The average amount of electricity consumed in U.S. homes has fallen to levels last seen more than a decade ago, back when the smartest device in people's pockets was a Palm pilot and anyone talking about a tablet was probably an archaeologist or a preacher.

Because of more energy-efficient housing, appliances and gadgets, power usage is on track to decline in 2013 for the third year in a row, to 10,819 kilowatt-hours per household, according to the Energy Information Administration.

That's the lowest level since 2001, when households averaged 10,535 kwh. And the drop has occurred even though our lives are more electrified.

Israel frees prisoners despite protests

JERUSALEM

- Israel has begun releasing more than two dozen Palestinian prisoners convicted in deadly attacks against Israelis.

Today's release is part of a U.S.-brokered package to restart Mideast peace talks. The prisoners are expected to receive a hero's welcome upon their return home.

In Israel, though, there is great anger and Prime Minister Benjamin Netanyahu has faced protests from relatives of the victims over the move. Under a formula drawn up by U.S. Secretary of State John Kerry, Israel agreed last summer to release a total of 104 long-serving Palestinian prisoners to restart peace talks with the Palestinians.

Dad of bomb suspect's pal writes prez

BOSTON

- The father of a Chechen man shot to death by authorities in Florida while being questioned in the Boston Marathon bombing investigation has written to President Obama asking for help finding out what happened.

Abdulbaki Todashev wrote in a letter released yesterday that son Ibragim Todashev knew dead marathon bombing suspect Tamerlan Tsarnaev and his brother, Dzhokhar Tsarnaev, through boxing but had no connection to the bombing or any other crime.

He said his son voluntarily went to an FBI office in Orlando to speak with agents four times before they showed up at his apartment on May 22. He included photos of his son's body with the letter and offered to travel to Washington, D.C., to speak to Obama directly. Attorney Barry Cohen said the elder Todashev, who lives in Russia, fears a cover-up.

Dzhokhar Tsarnaev has pleaded not guilty in the April 15 marathon bombing, which killed three people and injured more than 260 others. His brother died following a shootout with police.

A look at 2016: Who's doing what?

WASHINGTON

- Hillary Clinton as couch potato didn't last long. Was anyone surprised?

While she was getting back in the game, others who might run for president were in motion, too.

Republican Gov. Chris Christie socked away a big re-election victory in New Jersey and scored a prime position in his party to raise money and make friends.

Gov. Scott Walker, R-Wis., plugged a gaping hole in his resume with a new book. Rep. Paul Ryan, of Wisconsin, rode to the rescue as Republican broker of a December budget deal that avoided a repeat of the fall government shutdown.

Feds announce drone testing sites

LAS VEGAS

- Six states were named yesterday by federal officials to develop test sites for drones - a critical next step for the burgeoning industry that could one day produce thousands of unmanned aircraft for use by businesses, farmers and researchers.

Alaska, Nevada, New York, North Dakota, Texas and Virginia will host the research sites, providing diverse climates, geography and air traffic environments as the Federal Aviation Administration seeks to safely introduce commercial drones into U.S. airspace.

Members of Congress and other politicians lobbied intensely to bring the work to their states. Representatives were jubilant about the likelihood that the testing will draw companies interested in cashing in on the fledgling industry. An industry-commissioned study has predicted more than 70,000 jobs would develop in the first three years after Congress loosens drone restrictions on U.S. skies.

- Daily News wire services