People living near an active Hawaii lava flow have been warned to prepare for a possible evacuation in the next three to five days as molten rock oozed across a country road and edged closer to homes.
The flow is currently about 160 to 230ft wide and moving north east at about 10 yards an hour.
The lava 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 am local time. It is currently about six-tenths of a mile (1km) from Pahoa Village Road, the town’s main street.
It is 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.
Officials were visiting about 50 homes to keep residents informed of the lava’s movement, said Darryl Oliveira, director of civil defence for Hawaii County.
“This is all something we’ve been preparing for and hoping wouldn’t have to happen,” he 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.
The presence of hazardous materials, like a pile of tyres or a stockpile of chemicals, in the flow’s path would also trigger a mandatory evacuation order, he said.
Burning asphalt was generating some smoke, but Mr Oliveira said the wind dispersed the fumes over unpopulated areas and it did not pose a health risk at the moment.
Kilauea volcano has been erupting continuously since 1983. Most lava from this eruption has flowed south, but the lava has flowed to the north east over the past two years.
The current flow that has been threatening Pahoa began in June and has been moving towards 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 utility 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 governor Neil Abercrombie has asked for a presidential disaster declaration to get federal help for emergency crews.