Aizawl, Dec 20 : At least three workers were missing and feared dead after a stone quarry caved in at Pukzing area in Mizoram's Mamit district on Wednesday, officials said. The workers, all of whom hail from outside the state, were trapped under the debris which fell on them while they were working. District and the disaster management authorities immediately launch a rescue operation, which is still underway under the supervision of the senior officials. The officials are yet to disclose the cause of the accident, which occurred in the afternoon. The identities of the labourers are yet to be ascertained. On November 14 last year, 12 people died in a stone quarry accident at Maudhar area in Hnahthial district. The National Green Tribunal (NGT) registered a suo-moto case in the stone quarry collapse and had ordered a compensation of Rs 2.4 crore for the victims. /IANS