Masked robbers looted 32 kg of gold, worth several crores, from a bank in Chennai today evening after locking up the employees in a toilet.

The three masked robbers got hold of the keys of the strong room after entering FedBank Gold Loan in the city's Arumbakkam area and police suspect an insider is involved in the robbery.

"They took the keys and locked the employees in a toilet and escaped with the gold in carry bags. According to the branch, 32 kg gold was stolen," Police Commissioner Shankar Jeewal explained the modus operandi of the robbers.

"One of them is suspected to be a present employee of the branch," TS Anbu, Joint Commissioner of Police said.

"The inventory is being taken. Only after completion we would have the exact figure of the value of the stolen gold," he added.

The bank was closed today and only a few employees were present to do some accounts work.

A manhunt has been launched to nab the suspects.