The three senior Gujarat police officers arrested in connection with the killing of Sohrabuddin Sheikh in a fake encounter in 2005 refused cooperation when the police sought their consent for conducting narcoanalysis tests on them.

"The three, including DIG (border range) D G Vanzara, refused to undergo brain- mapping and other forensic tests when officials of CID (Crime) approached them for their consent," a police source told PTI on Friday night.

However, the CID officials are likely to approach the court on Saturday to seek permission for conducting the forensic tests, including narcoanalysis and brain-mapping.

The officials believe these tests will help them speed up their investigation, the sources said.

With the Supreme Court having directed the CID to submit a final status report on the case within two weeks, the investigating agency is keen to carry out these tests as soon as possible, sources said.

The CID officials had yesterday held a meeting with personnel of the Directorate of Forensic Science (DFS) in Gandhinagar in this connection.