Monsieur Pamplemousse and the Militant Midwives

Having delivered a particularly stirring speech at his recently deceased colleague's funeral, Monsieur Pamplemousse is more than a little disturbed when the coffin explodes into flames during the ceremony. Luckily his faithful hound Pommes Frites gives out a warning cry just in time so there are not casualties. But who exactly is behind this explosion?