People protest in front of Parliament building in Reykjavik, Iceland, on Tuesday. Iceland's prime minister resigned amid outrage over revelations he used such a shell company to shelter large sums while Iceland's economy was in crisis.

LONDON — Iceland’s prime minister became the first major figure brought down by the leak of millions of records on offshore accounts as the scrutiny intensified around officials from other countries, including Ukraine’s president.

Icelandic leader Sigmundur David Gunnlaugsson stepped aside Tuesday amid outrage over revelations he had used a shell company to shelter large sums while Iceland’s economy was in crisis.

Officials in several other countries also are facing questions about possibly dubious offshore tax-avoidance schemes, following the publication of the names of rich and powerful people linked to the leaks, dubbed the Panama Papers.

They include Ukraine President Petro Poroshenko who, the leaks show, set up an offshore holding company to move his candy business offshore, possibly depriving Ukraine of millions of dollars in tax revenue.

Poroshenko insists he has done nothing wrong and hasn’t managed his assets since being elected. Still, some adversaries are calling for his removal from office.

China and Russia, meanwhile, suppressed news of the leaks and rejected any allegations of impropriety by government officials named in the release of more than 11 million financial documents from a Panamanian law firm.

The reports are from a global group of news organizations working with the Washington-based International Consortium of Investigative Journalists. They have been processing records from the Mossack Fonseca law firm that were first leaked to a German newspaper.

One of the firm’s co-founders, Ramon Fonseca, said it has filed a complaint with Panamanian prosecutors, alleging that the data was stolen.