In Yemen, a day of rival demonstrations

Yemen's president, speaking to thousands of people at a pro-government demonstration on Friday, underscored his intentions to have a dialogue with protesters and make concessions in order to avoid bloodshed.

But President Ali Abdullah Saleh told the throng that while he's ready to hand over authority systematically, he said he won't do so to "gangs," "drug dealers" or the Houthi rebels fighting the government.

"We are against chaos and coups and against shooting one single bullet on our people," Saleh said. "We will hand over the authority to you great people."

As he spoke in Al-Sabeen Square, anti-government demonstrators gathered in another part of the capital in University Square.

The rival gatherings reflected the gulf in opinion throughout restive Yemen, a key U.S. ally and central battleground against al Qaeda that has been wracked by protests since the beginning of the year.

McLaren roar back into contention at Australian Grand Prix practice

McLaren's winter of discontent was banished in Melbourne as Jenson Button and Lewis Hamilton went quickest during second practice for Sunday's opening grand prix.

The British pair's preparation for the new season has been dogged by problems to their car with both pace and reliability an issue but recent tweaks to their design seem to have paid off.

Red Bull and Ferrari were tipped to dominate the season but McLaren gave notice of the impact they could have on the title race as Button posted a fastest lap time of one minute 25.852 seconds in the afternoon session with Hamilton just 0.132 secs behind.

Ferrari's Fernando Alonso wasn't far behind in third after a one minute 26.001 with defending world champion Sebastian Vettel, of Red Bull, ahead of teammate Mark Webber in fourth.

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Seven-time world champion Michael Schumacher was sixth in his Mercedes in an afternoon session hit by intermittent rain and wind.

After practice the 2009 world champion Button said: "Today showed that, first of all, we've got reliability -- which is great.

"That's something we've not had all winter, so to have a car that runs for as many laps as we want it to is very satisfying. It also means we can get stuck into our set-up work and improve the car.

Wildfire south of Denver 95 percent contained

Firefighters hope to put out the last of a wildfire that temporarily forced the evacuation of 8,500 people south of Denver.

The fire has burned 2 1/2 square miles of trees and grasslands near Franktown. Fire crews worked through the night and the fire was 95 percent contained Friday morning.

Authorities say the roof of one home was singed but no other damage was reported.

A helicopter was able to start dropping water on the blaze within about 15 minutes of the fire starting. Another helicopter and an airplane that had been fighting another fire in the foothills west of Golden also helped slow the growth of the latest fire.

Residents have been allowed back into their homes near Franktown but have been warned to remain ready to evacuate in case of flare-ups.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

Firefighters gained ground on two wildfires on the outer reaches of the Denver that forced thousands of people to flee their homes.

A fire fueled by high winds 2.5 square miles of trees and grasslands Thursday and prompted evacuation orders for about 8,500 people near Franktown, 35 miles southeast of Denver.

Japan reactor core may be leaking radioactive material, official says

Authorities in Japan raised the prospect Friday of a likely breach in the all-important containment vessel of the No. 3 reactor at the stricken Fukushima Daiichi nuclear power plant, a potentially ominous development in the race to prevent a large-scale release of radiation.

Contaminated water likely seeped through the containment vessel protecting from the reactor's core, said Hidehiko Nishiyama of the Japan nuclear and industrial safety agency.

Three men working inside the No. 3 reactor stepped into water this week that had 10,000 times the amount of radiation typical for that locale, Nishiyama said. That water likely indicates "some sort of leakage" from the reactor core, signaling a possible break of the containment vessel that houses the core.

The containment vessel is designed to prevent radioactive material from escaping into the atmosphere, even if other parts of the reactor are damaged. A rupture in the containment vessel could pose problems for workers who are trying to prevent that, depending on its severity.

The three workers who were exposed to radiation by stepping in the contaminated water had the highest levels of radiation recorded so far, said Tokyo Electric Power Co., which owns the plant.

The incident raised questions about radiation control measures at the plant as 536 people -- including government authorities and firefighters -- continued working there Friday, according to an official with Tokyo Electric.

Workers are undertaking various measures to prevent the further release of radioactive substances into the air and beyond.

Some 17 people have been exposed to 100 or more millisieverts of radiation since the plant's crisis began two weeks ago following a 9.0-magnitude earthquake and subsequent tsunami struck.

Obama juggles Libya promises, realities

The domestic political stakes of America's military intervention in Libya were raised Friday as the Obama administration worked to balance promises of a rapid U.S. transition to a supporting role with an apparent unwillingness among coalition partners to have NATO assume full control of the mission.

White House Press Secretary Jay Carney promised Thursday afternoon that U.S. military forces will be shifting to a "support and assist" role in the international coalition within a matter of days.

The United States is engaged in a "time-limited, scope-limited" action, Carney said.

Hours later, NATO Secretary-General Anders Fogh Rasmussen announced that NATO members will take over enforcement of the no-fly zone as early as Sunday. Rasmussen did not say, however, that NATO would assume the lead role in protecting civilians on the ground -- a role which has been mandated by the U.N. Security Council.

Rasmussen also did not say NATO would push to bring about regime change -- a goal beyond the scope of the U.N. mandate. U.S. officials have made clear that they want to see strongman Moammar Gadhafi removed from power.

The announcement raised questions about the prospect of a rapid, seamless transition from an American to a NATO-led operation.

So far, U.S. forces have taken on the bulk of the Libyan mission, according to figures provided by the Pentagon. Of a total of 175 Tomahawk missiles fired, 168 were from the United States and seven from Great Britain, the only two countries to possess them, while U.S. planes have flown almost two-thirds of the sorties and U.S. ships comprise more than two-thirds of the total involved.

A senior administration official asserted Thursday that details on the extent of NATO's mission were still being worked out.