The Central Reserve Police Force on Thursday found eight graves in the Communist Party of India-Marxist stronghold of Khejuri adjacent to Nandigram, three of which might contain human remains.
CRPF sources said the three graves found at Mansinghber on Thursday evening could be of women as torn pieces of a saree and bits of bangles and a necklace were found from there.
Five empty graves were located at Sherkhanchowk. A 25-member CRPF team have cordoned off the graves.
Earlier, the CRPF had found five graves in a field bordering a nullah on December 18 at Sherkhanchowk, the sources said.
A PTI correspondent, who went to the spot on Thursday, saw burnt wood and and portions of bicycle tyres lying around the shallow graves.
Local people alleged five bodies of CPI-M supporters killed while making bombs at a house there on October 28 were burnt at the spot and buried for a night before being taken away.
Anup Patra and Sukdeb Patra, both CPI-M supporters and residents of the village, claimed 19 Marxist supporters had been killed while making bombs at the house on October 28.
After the explosion, the bodies were taken away in two vehicles by Marxist supporters, he added.
One of the vehicles, with five bodies, offloaded them at the field where they were doused with kerosene and cremated on hastily-built pyres built of wood and bicycle tyres, Anup said.
That same night, the bodies were dug up and taken away, he said.
Earlier on December 6, human bones had been unearthed from five graves found by the CRPF at Bidyapith village in the Marxist stronghold of Khejuri.
The CBI also recovered bones after casting nets in the Talpati canal at Bhangabera in Nandigram during the same period.