 Meanwhile, in fall 623, Fu, after tricking Wang into surrendering his command and killing him, rebelled, claiming that Li Fuwei had been detained and had secretly ordered him to rise against Tang.Fu soon declared himself the Emperor of Song.In spring 624, Li Fuwei died suddenly—with official sources suggesting that he was poisoned by the substances he was taking as a part of alchemical exercises, but also, in a veiled manner, leaving open the possibility that he was assassinated on Emperor Gaozu's orders.