Kilauea volcano resumed erupting before dawn today within Halemaumau crater, U.S. Geological Survey officials said.

USGS’ Hawaiian Volcano Observatory said scientists detected a glow in Kilauea summit webcam images at 4:44 a.m., “indicating that an eruption has commenced within Halemaumau crater in Kilauea’s summit caldera, within Hawai‘i Volcanoes National Park.”

“The opening phases of eruptions are dynamic,” an HVO statement said. “Webcam imagery shows fissures at the base of Halemaumau crater generating lava flows on the surface of the crater floor. The activity is confined to Halemaumau and the hazards will be reassessed as the eruption progresses.”

HVO has elevated the Kilauea’s volcano alert level from “watch” to “warning” and its aviation color code from “orange” to “red.”

The volcanic activity is confined entirely within the park, officials said.

“The lava this morning is all confined within … the summit caldera. So plenty of room for it still to produce more without threatening any homes or infrastructure,” said park spokesperson Jessica Ferracane. “So that’s the way we like our eruptions here.”

She said park officials are bracing for crowds to arrive because visitors can see the eruption from many overlooks.

“Kilauea overlook was spectacular this morning,” she said of the vast lava lake. “It was molten red lava. There’s several areas of pretty robust fountaining. It’s just really, really pretty.”

Hawaii County Civil Defense officials said there is no volcanic threat to any community. “Due to the eruption, you can expect higher levels of volcanic gases and fine ash near the eruption site. Please take necessary precautions when near these areas,” they said in a community alert.

The National Weather Service in Honolulu said in a statement that winds will cause any ash emissions from the eruption to drift toward the west-southwest direction this morning.

“Communities in the Puna, Kau and South Kona Districts may be affected,” NWS officials said in a special weather statement. “Avoid excessive exposure to ash which is an eye and respiratory irritant. Those with respiratory sensitivities should take extra precaution to minimize exposure.”

The USGS also recorded dozens of small earthquakes in the summit region today with the largest at magnitude 3.4.

Kilauea is one of the world’s most active volcanoes. Its previous eruption, which was also confined to the summit caldera, ended March 7 after two months. For about two weeks in December, both Kilauea and Mauna Loa were erupting simultaneously, a rare event that threatened no residents or property but spurred a surge in tourism for Hawaii island.

Last month, Big Island residents marked the fifth anniversary of the start of Kilauea’s devastating Leilani Estates eruption which destroyed about 700 homes and structures, and caused hundreds of millions of dollars in damage.

Word was getting out about today’s eruption and parking lots were starting to fill up at the park, Ferracane said, adding that she expected long lines getting into the park by evening.

Since the park is open 24 hours a day, visitors can beat the crowds by visiting between 9 p.m. and sunrise, she said.

Ferracane reminded visitors to stay out of closed areas and remain on marked trails for safety reasons, including avoiding gases from the eruption.

The Associated Press contributed to this report.