Alaskan authorities monitor stirring volcano

(CNN) - A volcano in south-central Alaska could erupt within days or
weeks, authorities said.
"The level of seismic activity" has "increased markedly" in recent days
at Mount Redoubt, a 10,197-foot peak about 100 miles southwest of Anchorage,

the state's most populous city, according to the Alaska Volcano Observatory.

"We don't have a crystal ball," said Peter Cervelli, a research
geophysicist with the observatory. But "we expect based on the past behavior of
this volcano that this activity is going to culminate in an eruption."

The activity has consisted "of a combination of discrete, relatively

small earthquakes and periods of more continuous volcanic tremor." The activity
prompted the observatory to raise the alert level on Sunday, the observatory
said.

The volcano last erupted nearly 20 years ago, in December 1989, and

continued to April 1990. Geologists think there could be an eruption "similar
to or small than the one that occurred in 1989-90."

The eruption nearly two decades ago spread ash in Kenai, about 50 miles

west of the mountain, and in Anchorage. where it disrupted air traffic
operations. Cervelli said the ash plumes caused engine failure on a a jet
during that period.