By November 1937, there were claimed to be 15,000 anti-fascist prisoners in the Republic’s jails, about 1,000 of them from the POUM. The Right Opposition and other marxist groupings organised an international campaign in solidarity with the POUM prisoners which probably saved their leaders from a similar fate to Nin’s. The IBRSU also sent several delegations to Spain to visit the party’s prisoners and try to secure their release, the first headed by its General Secretary, Fenner Brockway. In August, another delegation arrived including the ILP MP James Maxton. A third delegation went in November headed by another ILP MP, John McGovern.