Seismologists confirm fourth earthquake in Missouri bootheel

LILBOURN, Mo. -- It happened again in the Missouri bootheel.

Seismologists confirm a fourth earthquake in southeast Missouri in the last week. The 2.4 magnitude earthquake was centered in the Lilbourn area. It hit about 9:35 a.m. Monday.

Last week, a 3.6 earthquake rocked the Caruthersville area. Two smaller earthquakes struck the Malden and Ironton areas.

The New Madrid fault zone is considered the most active east of the Rockies.