The research team suggests that what may have happened to cause the tsunami was a reverberation effect of an earthquake occurring along the Dead Sea Transform.
The Pacific Tsunami Warning Center initially said there was "no significant tsunami threat."
On the morning after Christmas Day in 2004, a 9.1 magnitude quake off northern Sumatra island triggered a tsunami with waves as high as 17.4 meters (57 feet) that swept over vulnerable coastal areas of Indonesia, Sri Lanka, India, Thailand and nine other countries.
Dubbed “Mighty Waves”, the drill began on Sunday and is scheduled to wrap up on Thursday.
Got a minute? Here's the week in review.
Images captured by the European Space Agency's Sentinel-1 satellite showed that a large portion on the southern flank of the volcano slid off into the ocean, scientists said.
Anak Krakatau, an active volcano roughly halfway between Java and Sumatra, has been spewing ash and lava for months. It erupted just after 9 p.m. on Saturday and the tsunami struck around 9:30 p.m.
The American Jewish Joint Distribution Committee (JDC) has planned to send emergency medical services and supplies to Indonesia after the Tsunami's aftermath.
The Red Cross said the situation was "nightmarish" and reports from its workers venturing into one cut-off area.
Hundreds had gathered for a festival on the beach in the city of Palu on Friday when waves as high as six meters (18 feet) smashed onshore.