A special team of the Mumbai police landed here on Monday evening to investigate the profile of the five suspected robbers gunned down in an encounter by the Chennai Police on February 23, police sources said.

Though the involvement of the prime suspect Sujay Kumar Rai alias Vinod Kumar of Patna in Bihar was confirmed in three bank dacoity cases in Mumbai reported in 2010, the team would check the identity and antecedents of the other four suspects to see if they were wanted by the Maharashtra police in connection with other cases, the sources said.

Teams of the Chennai police camping in Patna, Mumbai and Kolkata are coordinating with the local police there to check the identity of two others in the case. Of the five suspects, investigators have so far established the identity of three persons, including that of Rajeev Kumar of Nalanda in Bihar, who allegedly murdered a mutt head there in September 2009 and absconded.

One of the five pistols seized from the hideout of the suspects was suspected to be an imported one as it had the words ‘Made in USA' printed on it. The pistol, alleged to have been used by Sujay, was a sophisticated one. Investigation revealed that the suspects used a fake driving licence in Chennai. The driving licence with reference number ‘WB-11-1990' seized from their premises was purportedly issued by the licensing authority, Howrah, in the name of Abhay Kumar. However, the date of issue and expiry in the card was mentioned as ‘00/00/00'.

The Crime Branch CID on Monday took over investigation of the sensational police encounter case. Additional Director-General of Police N.P. Singh told The Hindu that Deputy Superintendent of Police Venkataraman was designated as the Chief Investigation Officer of the case. He would be assisted by several other teams, he said.