False Impression by Jeffrey Archer

When an aristocratic old lady is brutally murdered in her English country home on the night before September 11, 2001, it will take all the resources of the FBI and Interpol to work out the connection between her death and a priceless Van Gogh, which is stolen that night.
But in the end, it is a courageous young woman who escapes from North Tower of the World Trade Center after the first plane crashes into the building, who has the foresight and determination to take on both sides of the law and avenge the old lady's death.
The young woman, Anna Petrescu, takes advantage of being missing and presumed dead in the days after 9/11 to escape from New York City, only to be pursued by both the FBI and a ruthless assassin across the globe, from Toronto to London, to Hong Kong, Tokyo and Bucharest. But it is only when she finally returns to New York that the mystery unravels.