Millions of Londoners were exposed Monday to a series of anti-Israel posters on the underground network to mark the beginning of the Boycott, Divestment and Sanctions (BDS) movement’s 12th annual Israeli Apartheid Week.

Transport for London, which is responsible for the tube service, said this was “an act of vandalism,” the ads were not authorized and staff members were working to take them down, the Jewish Chronicle reported.

The posters, designed in the style of BBC reports, attacked the UK broadcasting organization [which is frequently criticized for pro-Palestinian leanings] for biased pro-Israel reporting and claimed Israel used British arms to “massacre Palestinians” during 2014’s Operation Protective Edge in Gaza.

A third poster criticized the global security company G4S for working in Israel, while a fourth, titled “Apartheid is Great….Britain,” alleged that more than 100 UK companies continue to supply military equipment to the Jewish State.

The Jewish Chronicle estimated that the ads appeared in some 500 trains.

A poster put up without permission in a London underground train on February 22, 2016 to mark the Boycott, Divest, Sanctions (BDS) movement's 12th anti-Israel Apartheid Week.

A poster put up without permission in a London underground train on February 22, 2016 to mark the Boycott, Divest, Sanctions (BDS) movement’s 12th anti-Israel Apartheid Week.

Israeli politicians on Monday afternoon argued over who it was that got the ads removed.

Prime Minister Benjamin Netanyahu said he asked Foreign Ministry chief Dore Gold, who is currently in London, to demand that the British government see to it that the offending posters were taken down.

MK Yair Lapid (Yesh Atid), by contrast, said he had contacted London Mayor Boris Johnson and asked him to intervene “because the government, as usual, was doing nothing.” Johnson, “a friend of Israel,” immediately took action, said the centrist opposition party leader. “He explained that they were put up without authorization and said he would give the instruction for them to be taken down immediately,” Lapid said.

Johnson lashed out against boycotters of Israel as “lefty academics” who wield no real influence, during a visit to Tel Aviv in November.

Dore Gold meanwhile told Army Radio that the issue had been dealt with before Israeli politicians intervened. Israeli embassy officials became aware of the posters around midnight Sunday and by first thing Monday, were talking with London’s council about having the adverts removed.

On Wednesday, the British government formally announced guidelines that prohibit publicly funded bodies from boycotting Israeli-made products. Bodies to which it applies include government agencies, the National Health Service and local authorities.