New Delhi, Aug 12 (IANS): The Lok Sabha was Thursday adjourned till noon after opposition members created an uproar over caste enumeration expected to be done at the biometric phase of Census 2011, saying it was a time-buying tactic.

Samajwadi Party (SP) leader Mulayam Singh Yadav and Rashtriya Janata Dal (RJD) chief Lalu Prasad raised the issue in the house as members assembled for the Question Hour at 11 a.m.

They were objecting to the decision of a group of ministers headed by Finance Minister Pranab Mukherjee on caste enumeration expected to be done at the biometric phase of the ongoing population census.

"Are they fooling us," Mulayam Singh shouted as Lalu Prasad tried to explain that the biometric process will take "100 years and will still not be completed".

The enumeration of caste in India has been evoking polarising response even as the pressure of other backward castes (OBC) groups forced the ministerial panel's nod.

However, it has not been resolved at what stage of the census would this be done even as sources Wednesday said the caste information could be recorded in the last stage of Census 2011 when biometric information will be gathered.

During this phase, biometric signs, including photographs, fingerprints and iris-mapping of citizens will be collected for the National Population Register (NPR) to create a multi-purpose unique identity card.

The first stage of the census - the household and family survey - is already over.

Janata Dal-United (JD-U) member Sharad Yadav also joined the protests, urging Speaker Meira Kumar to allow the protesting members to speak over the matter and ask the government to explain its position.

The speaker urged them to let the Question Hour proceed and raise the issue in Zero Hour. However, the SP, RJD and JD-U members walked towards her podium, forcing her to adjourn the house till noon.