Lucknow, July 18 - Union Coal Minister Sriprakash Jaiswal Saturday demanded a Central Bureau of Investigation (CBI) probe into the attack on Uttar Pradesh Congress chief Rita Bahuguna Joshi's house after her arrest for remarks against Chief Minister Mayawati.

'A CBI inquiry is the only option through which the reality can come to the fore,' Jaiswal said at a press conference at the Congress office here.

Joshi was arrested Wednesday for a speech against Mayawati that the chief minister said was insulting to her as a woman and a Dalit. Joshi was charged under the Scheduled Castes and Scheduled Tribes (Prevention of Atrocities) Act and sent to judicial custody for 14 days.

A mob shouting pro-Mayawati slogans attacked and torched Joshi's house in Lucknow around the time she was being arrested. The BSP denied its involvement in the arson.

However, Jaiswal said the attack on Joshi's house was a 'state sponsored conspiracy by misusing police machinery'.

'The state government should apologise at the earliest for the BSP workers resorting to vandalism and arson (at Joshi's residence),' the minister said.