"Prima facie, it appears that this is an instance of blatant use of disproportionate force resulting in loss of lives of 5 undertrials who were in judicial custody and gross violation of human rights", NHRC said in a statement.
The Commission has issued notices to the Chief Secretary and the Director General of Police, Telengana, calling for reports within two weeks.
It will further take up the matter in its camp sitting to be held at Hyderabad on April 23.
According to media reports, the incident took place when the vehicle carrying the undertrials crossed Warangal district border and reached the outskirts of Tangupuru village in Aler Mandal of Nalgonda district.
"One of the undertrials asked the police to halt the vehicle for a toilet break. While getting back to the van, he allegedly snatched an INSAS rifle from a policeman and fired two bullets at a Sub-Inspector sitting in the front row, who ducked and escaped. Sensing danger, other Constables immediately opened fire resulting in the instant death of five undertrials," the statement said.