11:17 a.m. Update:

Following a road closure that cut off the majority of drivers commuting to Anchorage along the Seward Highway, the road has been reopened and traffic began moving again at 11:17 a.m.

DOT personnel were on scene clearing debris for several hours after an early morning rock slide brought trees, boulders, and mud cascading down onto the roadway.

Officials say they do not know the extent of the damage, but that a 150 foot section of guard railing is still out.

A DOT spokesperson said that there was evidence that a vehicle had traveled through the debris, but there were no reports of injuries or damage connected to those attempting to traverse the slide.

A state geologist told DOT they believed the freeze and thaw action from this weekend may have contributed to the landslide.

9:00 a.m. Update:

The roadway is still fully blocked, closing the highway, and the Department of Transportation says it has no estimate for when the road will reopen.

According to a statement issued by DOT, crews from both the Anchorage and Girdwood sides are staged to begin work "once it's safe enough to start removing debris."

DOT says it has no estimate on when drivers can hope to drive through the highway.

The slide itself, according to estimates, is around 4 feet deep and 75 feet wide, spreading out along a sizable portion of roadway. DOT confirmed that the roadway reached the railroad tracks.

The Alaska Railroad is working on sending equipment to the site in order to clear the railroad tracks. No "noticeable" damage to the tracks was observed early Monday.

Original Story:

A landslide has blocked off a highly-traveled portion of the Seward Highway early Dec. 18, cutting off early morning commuters just before 6 a.m.

A witness, who told KTUU he was the first car in line at the scene, stopped right in front of a large slide of big trees, boulders, mud and rocks which covered both lanes of the highway.

An emergency advisory made by APD called it a "substantial rock slide across both lanes" of the Seward Highway. The area affected, between mile 105 and 107, is the so-called

.

The closure is a few miles north of Indian, cutting off those commuting from Girdwood and other communities into Anchorage Monday morning.

The Department of Transportation called it "impassible" and a "major landslide." DOT did not give any word on how long the road would be closed.

"Both lanes of travel is closed until further notice," the DOT said

The landslide also took out the guardrail, and poured over the railroad tracks, the witness told KTUU. Tim Sullivan, spokesperson for the Alaska Railroad, said that crews are on the scene now, and confirmed that the railroad tracks are impassible. He said it could be several hours before the tracks are cleared.

"It does not appear as though there is noticeable damage to the tracks right now," Sullivan said. "No trains have been delayed, we didn't have any scheduled down there this morning."

According to APD dispatchers, the Department of Transportation has been notified of the landslide, and will be responding to the area.

No injuries have been reported so far.

This is a developing story and will be updated.