Sri Lanka, July 19 -- A British tea heiress who abducted her two sons from their American father has been on the run in the UK for more than three months.

Nishika Samaratunga, 34, a scion to a Sri Lankan tea dynasty, is believed to be concealing the whereabouts of her two children, five-year-old Blaine Baier and Nathaniel Baier, known as Nate, who is three.

The boys were born in the United States and were being cared for by their father Ben Baier, who lives near Denver, Colorado.

Blaine and Nathaniel visited their mother in the UK in March as part of court-ordered contact following their parents' divorce, but Samaratunga failed to return them to Mr Baier at a UK airport on March 29.

She and the boys have not been located since.

Baier...