SAN FRANCISCO (AP) — A South Korean official says both U.S. and Korean investigators have been interviewing the pilots who were in the cockpit when an Asiana Airlines plane clipped a seawall before crash landing at San Francisco International Airport Saturday.

Two teenage passengers were killed.

A senior official for South Korea's Ministry of Land, Infrastructure and Transport says investigators from both countries questioned two of the four Asiana pilots on Monday, and they plan to interview the other two pilots as well as air controllers today.

The official says recorded conversation between the pilots and air controllers at the San Francisco airport also will be investigated.

Investigators already have said that the Boeing 777 had dropped below the threshold for a safe landing speed, but by the time the pilots realized it, it was too late to abort the landing.