In the absence of Railway Minister Mamata Banerjee in the Rajya Sabha, a Bahujan Samaj Party member described her junior E Ahammed as a "duplicate minister" on Friday.
The matter cropped up during the question hour when Ahammed was responding to supplementaries of Naresh Agarwal of the BSP.
Not satisfied with Ahammed's reply, Agarwal said he was a "duplicate minister".
The remark enraged Minister of State for Health Dinesh Trivedi, who belongs to Banerjee's party -- the Trinamool Congress.
"How do you call him (Ahammed) a duplicate?" Trivedi asked.
This led to protests from opposition members who asked as to how Trivedi, who is a minister and not a member of the Upper House, could intervene.
To this, Trivedi said he was replying on behalf of the government.
Trivedi was supported by Congress members leading to a wordy duel, prompting Rajya Sabha Chairman Hamid Ansari to ask members to maintain order.
Replying to another question, Ahammed defended Chairman of the Railway Board Vivek Sahai for his statement that the Sainthia train mishap in West Bengal could have been due to human error, indirectly referring to the driver of Uttar Banga Express.
"I don't agree that the chairman of railway board exceeded his limits. It was his duty to brief the media after the accident. Whatever he said were the views of the railways. He is competent to speak," he said.
The minister said the mishap is being probed from all possible angles. The ministry of railways has also asked for an enquiry by the Central Bureau of Investigation into the incident.
