New Delhi, Apr. 25: The Election Commission of India on Saturday issued a notice to senior Congress leader Digvijay Singh for violating the Model Code of Conduct.

The commission's notice said that Singh would need to explain his adverse comments against Uttar Pradesh Chief Minister Mayawati.

Mayawati is said to have lodged a complaint with the Election Commission against the former Madhya Pradesh Chief Minister for seeking to invoke the use of the Central Bureau Investigation to warn her ruling Bahujan Samaj Party against harassing Congress workers in Uttar Pradesh.

Singh's threat was issued at an election rally in Hardoi, Central UP, and invited an immediate reaction from Mayawati and the BJP, which has been accusing Congress of devaluing crucial institutions such as the Election Commission, CBI and the Rashtrapati Bhawan.

The Opposition saw Singh's remarks as a vindication of its stand that CBI had become a mere tool in the hands of the principal ruling party to harass its political opponents.

Singh warned the BSP leadership against harassing state Congress leaders.

"I am challenging and warning the BSP leadership against victimising our party workers. Mayawati should not harass our party members as she has a CBI case pending against her and when we form the next government she will be in trouble," he told the rally.

Singh's remarks had his party colleagues scurrying for cover, but BSP and BJP pounced on them to corner Congress.

Mayawati, while addressing newspersons in Lucknow, spoke about how CBI was being used to threaten her. BJP, on the other hand, came out with a "we told you so" response.

Singh subsequently came out with a clarification.

"There is no question of any kind of threat. There have been a lot of complaints of Congress workers being harassed and falsely implicated in criminal cases in UP," he said. (ANI)