Mola, Franco's second-in-command, was killed on 3 June, in an airplane accident. In early July, despite the earlier loss at the Battle of Bilbao, the government launched a strong counter-offensive to the west of Madrid, focusing on Brunete. The Battle of Brunete, however, was a significant defeat for the Republic, which lost many of its most accomplished troops. The offensive led to an advance of , and left 25,000 Republican casualties.