IMF Managing Director Lagarde was speaking to students about the European debt crisis when organised students mixed in with the audience began interrupting pre-approved questions, apparently with criticism of the fund's policies.
Security guards grabbed several students leading the chants, which began with the sneer "Madame Lagarde!", and dragged them away from the building's lobby, where the interview is continuing.
Lagarde said she currently spends about half her time addressing problems in Europe.
The 17-country eurozone is in recession, and Lagarde and an increasing number of economists are criticising a German-led drive for other governments to get their budget deficits under 3 per cent as soon as possible.