Straits of Malacca
There were posts a long time ago asking the same question as to why the US was searching the Straits of Malacca.
Some answers were:
They have a P-3 base nearby and do regular SAR training.
One of the interested countries asked the US to search that particular area.
Someone knows something and wants to get their stories and evidence straight.
I know that last one entails a conspiracy, but this is a rumor network.