India, May 28 -- Assam chief minister Himanta Biswa Sarma on Wednesday stepped up his attack on Congress MP Gaurav Gogoi, claiming that he had documents to establish that Gogoi and his wife were "deeply into anti-India activities".

Sarma also claimed that he had documents to back his allegations against Gogoi, who was appointed Assam Congress president on Monday, and his British wife, Elizabeth but would only make them public on September 10 after an ongoing probe by a special investigation team (SIT) of the state police into the allegations is completed.

"I have documents to prove that his wife is involved in collecting various intelligence inputs of Government of India on behalf of a climate lobby. On September 10, I am going to revea...