The alleged kingpin of the gang that looted Rs 10 lakh from a guard of Anandalok Hospital, Salt Lake, was arrested in a village in Bhangar, South 24-Parganas, on Thursday night.

?Tapan Mondal, alias Sadhu, had masterminded the armed dacoity on November 16 in the township?s DK Block. We have recovered Rs 79,000 from his residence,? said additional superintendent of South 24-Parganas police B.C. Mondal.

?Tapan had been arrested several times for dacoity. We are interrogating him about his accomplices, as well as where the rest of the loot has been hidden,? Mondal added.

The raid was led by Mainak Banerjee, officer-in-charge of Calcutta Leather Complex police station.

An armed gang of six, in a blue Maruti Omni, had ambushed the Qualis in which the hospital guard was travelling with Rs 9.73 lakh and cheques for Rs 78,000 in a bag.

The gang members attacked the guard and the driver, severely injuring them, and made off with the money as well as the Qualis key.

The CID took over the case the next day. A few days later, the sleuths arrested three persons, including a Class IV employee of the hospital, and recovered Rs 1.26 lakh. The Omni, too, was impounded.

Senior officers believe Tapan holds the key to the case. Salt Lake sub-divisional police officer Kanad Mukherjee is in the team that is grilling Tapan about the heist.

The Thursday night raid was preceded by a tip-off. The criminal, however, made the police team chase him for more than a kilometre before he ran out of breath and tripped.