The incident took place near Mogra village under Muffasil police station as some motorcycle-borne assailants fired at Jamir Lal Oraon and his wife Neelam Oraon while they were on a motorbike, SDPO Rakesh Kumar said.
While the 30-year-old woman died on the spot, her husband, aged about 35 years, sustained injuries and was hospitalised in a critical condition, he said.
One of the two assailants, identified as Suresh Yadav has been arrested, while raids were being carried out to nab the other, Kumar said.