HONOLULU - Flowing lava from an erupting volcano could soon force dozens of residents of an area in Hawaii to flee their homes.
Authorities on Saturday told them to prepare for a possible evacuation in the next three to five days as the molten rock oozed across a country road and edged closer to homes.
The flow was about 35 yards wide and moving northeast at about 10 yards per hour.
Lava of some 2,000 degrees Fahrenheit crossed a road on the edge of Pahoa, the largest town in the mostly rural region of Puna on the Big Island of Hawaii, at 3:50 a.m.
It was about six-tenths of a mile from Pahoa Village Road, the town's main street.
It's not clear when it might reach the village road as the flow has been advancing erratically, said Matt Patrick, a geologist with the Hawaiian Volcano Observatory.
Kilauea volcano has been erupting continuously since 1983. Most lava from this eruption has flowed south, enveloping the Kalapana and Royal Garden residential subdivisions as it poured out to sea.
For the past two years, however, the lava has been flowing to the northeast, bringing it to Pahoa's doorsteps.
Officials were going door-to door to about 50 homes to keep residents informed of the lava's movement, said Darryl Oliveira, the director of civil defense for Hawaii County.
"This is all something we've been preparing for and hoping wouldn't have to happen," Oliveira said.
The county will issue a mandatory evacuation order if the flow begins advancing at such a rate that it would be difficult for people to move out of the way with little notice, Oliveira said.
Burning asphalt was generating some smoke, but Oliveira said the wind dispersed the fumes over unpopulated areas and it didn't pose a health risk at the moment.
Oliveira said the current situation differs from the flows of past decades because the lava is now approaching the center of a community. Pahoa is not only more densely populated, he said, but it also has commercial and industrial sites as well as residential homes.
The current flow that has been threatening Pahoa began in June. It's been moving fitfully toward the town for weeks, speeding up and then slowing down.
Sporadic suspensions in the lava's movement gave emergency crews time to work on building alternate routes to town in the event the flow covers the main road and highway.
Crews near the leading edge have been wrapping power poles with concrete rings as a layer of protection from the lava's heat.
The lava's pace picked up in recent days when it reached a gully, allowing it to move more efficiently like rain in a gutter.
Hawaii Gov. Neil Abercrombie on Friday asked for a presidential disaster declaration to enable federal help for local emergency crews.
Mayor Billy Kenoi has already declared an emergency, which allows authorities to restrict access to roadways so Kaohe Homesteads residents can leave safely if an evacuation becomes necessary.
The emergency declaration allows the county to restrict access to certain areas to ease preparation for residents. The declaration does not mean an evacuation has been ordered, reports CBS affiliate KGMB.