Two workers were seriously injured when crushed by a 12-metre beam at a roadside trench yesterday in Tsim Sha Tsui. The accident happened when the beam was being lowered into the 8-metre deep trench by a crane in Salisbury Road at 6.45am. Police said a chain holding the beam broke and it fell onto the workers. The two men, both 47, were trapped under the beam, and firefighters struggled for 15 minutes to free them. A police spokeswoman said one of the victims had lost consciousness while being carried to an ambulance. Both were in a serious condition last night in Queen Elizabeth Hospital. The Labour Department is investigating.