What is the fine-grained topic of the following text: Nguyen Thi Minh Loan, 56, was arrested at Tan Son Nhat International Airport at 10 p.m. on May 18, 2012 when custom officers found five packs of white powder in her luggage before was able to board a flight to Sydney. Only return the topic.
Arrest of Nguyen Thi Minh Loan for drug possession at Tan Son Nhat International Airport