FAA: 4 dead in Sioux Falls small-plane crash

Updated 8:42 PM ET

SIOUX FALLS, S.D. - Four people are dead following a plane crash near the Sioux Falls Regional Airport, a spokesman with the Federal Aviation Administration has confirmed.

Tony Molinaro says the plane was a Cessna 421-C. The small, two-engine plane departed Joe Foss Field at 2:24 p.m. and was headed to Rapid City. It crashed soon after takeoff about a mile west of the field, he says.

A witness told CBS affiliate KELO Sioux Falls that plane headed straight to the ground and exploded, and that smoke was coming out of the plane

Two of the four people who died have been identified.

Augustana College in Sioux Falls, S.D., confirmed late Friday that Dr. Daniel Swets, associate professor of computer science, and Kevin Anderson, an alumnus of Augustana, were among the four people killed in the crash.

The two other people have not been identified.

Police and fire crews are at the site. Molinaro says that the FAA is handing over the investigation to local law enforcement, as is standard with fatal plane crashes.

Authorities say they do not yet know what the trouble was.